werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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Just a couple alignment tips here.
1/ if your Nexstar does not have index pointers for getting the ota orthagonal(perpendicular to the vertical axis of the mount) make some. It's easy, and speeds up the alignment process.
2/ Most of the time, a 2-star alignment well done is just as accurate as the auto-align, and simpler to do. No lat/long entries to do, no finding North. However, if you use the 2-star method, it will NOT goto the moon/planets unless you go into the Menu, and input date/time.
3/ Best Pair is a great little Windows app for determining the best alignment stars for a given time/evening.
4/ Speaking of Alignment Stars, don't do what I was doing, and assume that the ones the scope would choose are the best ones. Sometimes they are, sometimes they aren't. Play with it a little. For example with my N8, the old Vega-Arcturus pair is OK if you want to explore in, and around Lyra, but Altair-Arcturus gives better accuracy in, and around Cygnus, and coincidentally U Major.
5/ This is a big secret here: You DON'T have to use the goto universally! Yes, it's a great tool, but not critical. Try it the old fashioned way. Find your brighter objects with the star-pointer/finderscope. Starhop with it. Have fun. Above all, keep you sense of humor alive.
6/ That star-pointer can be replace with a magnifying finderscope relatively cheaply. No batteries to mess with, and it can help tweak a missed goto into view.
Just some tips for newb, and oldster alike. Pete 
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
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square_peg
Postmaster
Reged: 03/26/04
Posts: 29505
Loc: Maple Valley, WA
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Quote:
...
3/ Best Pair is a great little Windows app for determining the best alignment stars for a given time/evening.
...
Just some tips for newb, and oldster alike. Pete
Is 'Best Pair' available as freeware/shareware somewhere?
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Tom (Pegster)
DSH-8 (GSO Dob)
15x70 Oberwerks
SVP/ED80
WO 66 Petzval
Sears Discoverer EQ 60/900
8x42 Regals
History is Philosophy teaching by examples.
Thucydides
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b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
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You can get "Best Pair" at http://www.ilangainc.com/bestpair/
It is "freeware" but they ask that you register it.
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"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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Sorry about that, my bad. I got mine from Michael Swanson's Nexstar site. Address is www.Nexstarsite.com . Pete
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
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Michael_Swanson
super member
Reged: 04/23/03
Posts: 189
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Hi Pete,
Do you mean to say you got the software to suggest alignment stars at my site? If so, you were either suggesting Jean Piquette's program for generating suggested lists of alignment stars (found in the Downloads section) or NexStar Observer List which suggests stars on the Alignment Star Chart (which can also be printed - both the all sky charts and the suggested pairs). Both are freeware.
Best regards,
Mike Swanson
Author of "The NexStar User's Guide"
Author of "NexStar Observer List"
http://www.NexStarSite.com
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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Michael, I was speaking of Mr. Piquette's software. Extremely useful piece of code. Thank you for chipping in here sir. I will of course defer to your expertise with the Nexstar Series.  Pete
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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Wow! Can I kill a thread, or what? Pete
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
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square_peg
Postmaster
Reged: 03/26/04
Posts: 29505
Loc: Maple Valley, WA
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Sometimes us little dogs have to fill in till the big dogs get here. Mike is Da Man when it comes to Nexstars. His site got me off to a good start. Still refer back to it when I'm not on CN.
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Tom (Pegster)
DSH-8 (GSO Dob)
15x70 Oberwerks
SVP/ED80
WO 66 Petzval
Sears Discoverer EQ 60/900
8x42 Regals
History is Philosophy teaching by examples.
Thucydides
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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I have gotten a lot of good stuff off of Mike's site. I just figured a sticky with what I know would be helpful. If any of y'all got any tips feel free to chip in. share the wealth! Pete
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
Edited by werewolf6977 (07/31/04 08:17 AM)
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square_peg
Postmaster
Reged: 03/26/04
Posts: 29505
Loc: Maple Valley, WA
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Agreed. Yours is a great list of alignment tips and will be very helpful for Nexstar users. The order of the tips is correct, too. Make orthagonal marks and do two-star aligns. I made my marks shortly before the Table Mountain Star Party. With just a two-star alignment, every Messier Object I attempted was in the FOV (near center) of my 30mm Ultima at 33×. That method really works great.
One thing I might add to your list is the importance of aligning the red-dot star pointer. This is easily done during the daytime by using an 'artificial star' like the red light on top of a radio antenna tower. With the pointer properly aligned, most objects are easy to find without goto (much more fun). Carefully study the objects position on a star chart and aim your pointer accordingly. If it's not in the FOV, try drawing imaginary lines through neighboring stars to more accuratlely place the red dot. This will help you learn the constellations and the names of stars to use in future two-star alignments.
Great thread, Werewolf! 
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Tom (Pegster)
DSH-8 (GSO Dob)
15x70 Oberwerks
SVP/ED80
WO 66 Petzval
Sears Discoverer EQ 60/900
8x42 Regals
History is Philosophy teaching by examples.
Thucydides
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markf
Carpal Tunnel
Reged: 10/13/04
Posts: 1935
Loc: Houston, TX
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Quote:
4/ Speaking of Alignment Stars, don't do what I was doing, and assume that the ones the scope would choose are the best ones. Sometimes they are, sometimes they aren't. Play with it a little. For example with my N8, the old Vega-Arcturus pair is OK if you want to explore in, and around Lyra, but Altair-Arcturus gives better accuracy in, and around Cygnus, and coincidentally U Major.
Pete,
Can you expand on this? Is GOTO only acurate for certain constellations, depending on the alignment stars you choose?
Mark
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Celestron C6N on a CG5-GT
Orion 80mm Refractor (guidescope)
ToUCam Pro II
Canon Digital Rebel
http://www.carsandfish.com/astroweb
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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Mark see my response to your next post.
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
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Anonymous
Unregistered
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Is there any way I can find out the Latitude and Longitude of where I live? For when I Align My scope?
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rustynpp
Pooh-Bah
Reged: 08/27/04
Posts: 1011
Loc: Rye, NY
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Quote:
Is there any way I can find out the Latitude and Longitude of where I live? For when I Align My scope?
I love this site. It's amazing how useful it is.
http://www.zipinfo.com/search/zipcode.htm
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Nick P
N8i
Nikon 10x50
PST-SM40
Rye, NY
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Anonymous
Unregistered
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Quote:
Quote:
Is there any way I can find out the Latitude and Longitude of where I live? For when I Align My scope?
I love this site. It's amazing how useful it is.
http://www.zipinfo.com/search/zipcode.htm
Thanks, I should have said but I live in England so I can't use that site! Thanks anyway 
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werewolf6977
Lord High Smasher
Reged: 12/15/03
Posts: 8431
Loc: Hanover, Ohio
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I think Skies Above can help. run a Google, and see what you find. Pete
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Pete
6" Apogee/LXD55
Starhopper 6" Dob
Spaceprobe 130EQ
Black C8 OTA
WO Zenith Star 66 Patriot Edition
Sun Pak Pro 7500 Platinum Edition
8X42 Bushnell H2O Porro
7X35 Tasco
10X50 Nikon Actions (Type 7)
15X70 Skymasters
Dell Inspiron Dual Core 531s
"Science without Religion is lame, Religion without Science is blind" A.Einstein.
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Anonymous
Unregistered
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X: 419400m Y: 560000m
Lat: 54:56:03N (54.9343) Lon: 1:41:53W (-1.6981)
Thats what I get but how do I enter that into my HC as it displays a differnt format.
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Anonymous
Unregistered
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I think you have what you need there. 54 deg, 56 min 3 sec North, 1 deg, 41 min, 53 sec W.
FYI - for simple coordinate conversions, I use this freebie.. http://www.mentorsoftwareinc.com/freebie/FREE1198.HTM
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haleymon
Pooh-Bah
Reged: 09/10/05
Posts: 1234
Loc: Spring, Texas N.W. of Houston
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This was a GREAT thread I leard quite a bit
Thanks Guys
Dave
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Clear Skies to all
Dave
Celestron CPC 800 XLT
2" Astro Tech Dielectric Diag.
Orion Shorty Plus Barlow
Telrad
Canon 40D DSLR (On Its Way)
NexImage w/LE Mod
Starry Night Pro 5.0
5mw GLP
-------Haley's Haven Observatory-------
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Chris Emley
member
Reged: 04/24/04
Posts: 17
Loc: San Francisco, Marin
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You oughta try Google Earth (a free download from Google). I gives aerial surveys of most of the globe. I found my own backyard on it, centered the cursor on the concrete pad where I set up to stargaze, and read the very precise coordinates. Sure improved my Goto results!
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NexStar 8 with 8i controller & base
Denk Std with Dual Power Switch
19mm Panoptics
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HughBoy
sage
Reged: 09/08/04
Posts: 427
Loc: Durham, NC
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Mike has updated the info on alignment to include the later models/versions (with SkyAlign, etc.).
http://www.nexstarsite.com/AlignmentFAQ.htm
Also, there's a helpful PDF: "The NexStar Alignment Guide".
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Hughboy
- Coronado PST ("Goldeneye")
- WO ZS66 SD APO ("The Pocket Rocket")
- Celestron C80ED APO ("The Sleek Black Beauty")
- Celestron C8 SB-XLT ("The Pony Keg")
-- WO binoviewers
-- Imaging: Canon DSLR, Nikon Coolpix 4500 w/Scopetronix EP, Meade LPI
> ASGT, NexStar GT/BaaderBracket, SVP, EQ-1, Bogen 3001D/410 geared-head
(and too many old POS scopes to mention...)
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amys
Carpal Tunnel
Reged: 06/12/06
Posts: 2203
Loc: Groton, CT
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you can get lat/ long for your zipcode or town at http://www.zipinfo.com and for your street address at www.geocode.com.
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Amy
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JHollJr
sage
Reged: 06/10/06
Posts: 204
Loc: Quantico, Virginia
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Strangely enough, when I enter my coordinates from Google Earth the goto isn't as good as when I enter the city that is about 4 miles south of me. Go figure.
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Justin
Northern Virginia
Celestron Nexstar 8i SE
Questar 3.5 purchased 1980
Leica Ultravid 10x50's
Oberwerk 20x80 Ultra Lights
UA UniMount Light Deluxe
Horrible Eyes
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Leo1
scholastic sledgehammer
Reged: 06/07/06
Posts: 918
Loc: Central Kentucky, USA
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I purschased my NexStar 8i in October 2003. I still use the same handset that came with the scope. I did purchase the CN11 GPS. I've heard about the newer handsets and claims that they are better for the alignment. But when I research into it, it just seems that my old one is better???? I only have to turn it on and press align. The scope then levels the OTA and slews to the north. Makes contact with the satelites and receives time and location. It then automatically slews to the first alignment star where I center it in the star finder and press enter then I center it in the eyepiece and press align. It then slews automatically to another star and I repeat the centering and press : align. It then says to wait a moment while it analyises the information then it will tell me "alignment successful" or "unsuccessfull. Ninety-eight percent of the time it will be a successfull alignment. This just seems a little easier to do than the newer ones????? 
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Celestron NexStar 8i
Celestron 9.25 XLT CPC
Celestron Onyx 80EDF Piggy-backed on the CPC
JMI EV2CM Motor Focuser
Astro-Tech 2inch Diagonal
TeleVue 13mm Nagler 6
Televue 11mm Nagler 6
Stardust Observing Chair
TMB 9mm Planetary
TMB 3.2 Planetary
JMI Wheeley w/5 inch wheels
Kendrick Dew Remover Model VI
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b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
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I think the biggest difference in the old "north and level" and the new "sky align" systems, as far as accuracy of alignment are pretty small. The biggest difference between the two is with the older style you have to be able to identify the star that the scope THINKS it's slewing to and then center it up. With the new version you just center up any two prominent objects in the sky (stars, planets, or a combination of both) and it figures out what you've pointed at for you and does the alignment.
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"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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KidNme
super member
Reged: 12/14/06
Posts: 107
Loc: Southeastern PA
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I have a Garmin GPS and input my exact viewing site into the scope, including elevation. I'm also inputting the nuclear clock time. Once I do a 2 star align, I should be able to "GoTo" anything in the sky shouldn't I? Starry night seems to be right on target. I've seen satalites on my PC then ran outside and found them in my binocs right where and when it said it would be. I would imagine that this would translate into the "goto" of the scope and be as accurate right?
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Celestron Starseeker 130mm GoTo Reflector
Bunch of EP's & Filters
10X50 Nikkon Action Binoculars
Starry night pro v.6
Narry a clue! ;-)
"2nd Star on the right and Straight on till morning!"
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mufoi
member
Reged: 04/19/07
Posts: 75
Loc: Victorville, CA
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Thank you for the software suggestion. I will try it out when I get my scope tomorrow and when the sky clears up.
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Digital Engineer for the Deep Space Network
NexStar 8SE
Powertank 17
Various Celestron eyepieces and filters
Nikon D40x
Celestron 10x50 binoculars
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Hal Pollner
Reged: 08/30/05
Posts: 6567
Loc: Southern California Desert
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Is Michael Swanson the "Mike" you are all referring to as the NexStar expert?
HAL
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spaceydee
Postmaster
Reged: 04/16/04
Posts: 16125
Loc: Where the Kittens Are
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He is.
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Dee
space-scientist
student violinist
Nexstar8i,SV80S,80/9D,FC100,94 Brandon,TMB92SS,GM8
8" f/7 Discovery,12.5" Portaball, PST
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nexstar8
member
Reged: 05/26/07
Posts: 20
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Nothing was mentioned about a level tripod. Is this something I'm putting time into which is not necessary.
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Nexstar 8SE
Pentax 14XW
Televue 24 Panoptic
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nexstar8
member
Reged: 05/26/07
Posts: 20
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Nothing was mentioned about leveling the tripod. Is this something I wasting my time on needlessly?
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Nexstar 8SE
Pentax 14XW
Televue 24 Panoptic
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mclewis1
Thread Killer
Reged: 02/25/06
Posts: 3950
Loc: New Brunswick, Canada
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Most of us find that eyeball close is good enough for an evening of gotos. There are times when I spend a little time and use a level on my NS11 tripod ... usually when I expect to be out for more than a few hours.
Try just guessing at level for a while and see if your tracking and pointing are still reasonably accurate, if so you'll save yourself a little time each evening. If not you'll have proved to yourself the value of those few minutes you spend on leveling.
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Mark
C11, C6, APM/TMB115, and AT80ED - Tandem mount CGE and CG-5A, WO EZ-Touch and AT Voyager
25x100s and 8x56s, T-Mount Light, Mark 1 eyeballs - Modded 350D, DSI-P, SPC900, Mallincam
Just because you can doesn't necessarily mean that you should
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nexstar8
member
Reged: 05/26/07
Posts: 20
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What about leveling the tripod. Is this important?
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Nexstar 8SE
Pentax 14XW
Televue 24 Panoptic
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BBishop54
sage
Reged: 06/08/07
Posts: 247
Loc: Upstate N.Y.
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I'd level it each time if I were you. It makes it that more accurate.
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David Bishop
Nexstar 6SE
The conquest of space is worth the risk of life.
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b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
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I have one of the $2.99 "Bullseye" round levels from Home Depot that I use to level my tripod every time I set it up. I used to level the tripod and then double check the scope base, but I've found (using the Starizona "Landing Pad") the double check isn't necessary.
I know I supposedly don't have to be that accurate to get good gotos. But, I'm an engineer and it's just the way we are...
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"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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Clint M
member
Reged: 06/03/07
Posts: 28
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Just a quick question - not sure if this is off-topic or not, but didn't seem worth starting my own thread.
I was aligning my scope tonight, and a thought crossed my mind. I had just added an Orion 9x50 finder scope to my scope, and while there's not a lot of weight on it, it got me thinking: Would the added weight cause any problems with tracking or aligning? Would the motor/electronics "know" the extra weight was there and compensate for it?
Thanks --
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Clint
Madison, WI
NexStar 8SE
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b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
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A little "off topic" but reasonable.
No, that amount of weight won't bother it for tracking. You don't list what kind of scope you have, if it's a GEM, just balance the scope with everything attached. If it's a fork mount, no problem, just be sure your clutches are tight. I wouldn't add much more than the finder, but it's not going to hurt you.
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"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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Clint M
member
Reged: 06/03/07
Posts: 28
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Sorry - it's an 8SE. Thanks for the reply, Randy!
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Clint
Madison, WI
NexStar 8SE
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Clint, just to add a little to what Randy said, and at the risk of stll being off topic, you can add extra weight to the 'scope without too much problem (Randy didn't know at the time what you were using).
This is my N8i which, because the OTA was originally solidly fixed to the mount arm I added a Ray's bracket so that it now clears the base. (The original design was in my view, poor but you've now got the flexibility with that dovetail fitting on the 8SE).
http://s151.photobucket.com/albums/s121/Tel_album/BacktoNature.jpg
On top of this, therefore, it also sports a 9X50mm finder, a dew shield, as you can clearly see and a 2" diagonal plus EPs.
I think you'll find your 'scope is similarly tolerant to additional weight but just don't overdo it.
Regards,
Tel
BTW. The flowers etc. in the photo come free !
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Truth is the cubed root of Verbosity.
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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PS. Forgot to mention that it will also support a 6.3 or 3,3 Focal Reducer (need to shift the OTA a little more to the front with these in combination with a 2" diagonal so as to clear the base) and, as you can see from the photo, a motorised focuser.
Tel
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Truth is the cubed root of Verbosity.
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Jase
newbie
Reged: 10/08/07
Posts: 4
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Apologies if this has been asked before, but I wore the search out and did not find an answer. Since this has to do with alignment, I'm posting it here instead of creating a new thread. Hope that is alright.
I have a NexStar 5 SE and my question is with minimizing backlash. The manual states to use the final directions of the GoTo approach when centering using the example of "right" and "up". Is this universal for all 5 SEs or do "the final directions" vary from scope to scope? It also states that when the slew speed is 6 or below, "up" and "down" switch.
So when I center, I want to use the "right" and "up" buttons if I am at a slew rate greater than 6. Otherwise I use "right" and "down" buttons. Is this correct?
Edited by Jase (10/10/07 03:56 PM)
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Jase and welcome to CN !
You seem to be asking some questions here which need firstly to be addressed before their answers can be put together to provide you with what you seem to seek, namely good GoTOs and tracking for each object you choose to view.
Firstly though, I must point out that I am used to setting up the 8" rather than the 5" 'scopes of the SE series but in principle the same rules should apply.
Stage by stage then, let's cover the basics. I would approach things initially according to the following. However, if something doesn't work, I will need you to tell me so that I can modify the procedure.
1) Set your "GoTo Approach" to negative on the altitude axis and positive on the azimuth axis. (The altitude axis might need changing to positive if negative doesn't work but negative is the default and is normally relevant to nose heavy or neutral balance 'scopes like the 5SE. A positive azimuth axis should always be the case for northern hemisphere users).
2)Now to set up the scope's antibacklash. Firstly remember, there is no magic standard setting. All 'scopes are individual. Thus, work on one axis at a time. Point the 'scope in daylight at an object (a brick wall is good because it will give you a grid pattern).
Don't worry about high slew speeds at all (they will take care of themselves)but just concentrate on those you will need to move an object around in the eyepiece.
So, work on speeds say, 5 down to 2. Raise and lower the image of say the brick wall grid in the EP at the various slew speeds with reversals of the motion until the action is smooth on both the Alt. and Az. axes. Some delays, proportional to the chosen slew speed, will inevitably occur while the motors reverse themselves prior to making the slew but so long as these amount to say less than 10-15 secs., accept this as being of no consequence.
3) OK, now you should be ready to align. Set up your time site etc. and also make a "Calibrate GoTo". I will use the "Auto Two Star Align" for the purpose of this exercise and make the assumption you are using a red dot finder.
4) Let's assume you choose Altair as your first star. As required, you will need to manually slew to it. To get it in the sights of the RDF you will probably need initially to use the higher slew speeds which as you say are reversed from 6 upwards but you'll soon figure out which button to press to get Altair on the RDF without thinking about reversals. Let's face it, you see the star, you slew to it. If you're slewing away from it you hit the correct button !
5) OK so now you have Altair in the RDF and also somewhere in the FOV of the EP (use a 20mm or 25mm).Now you need to centralise it. Use in this case, the recommended right and up buttons in combination with a low slew speed. (Anything higher than 5 will be too fast and even at 5 you might not be able to control sufficiently. (I tend to use 4 and 3). Also centralise on a somewhat defocussed image. With the appearance of a doughnut rather than a pinpoint of light in the EP, centralisation is so much easier.
6)Once centralised in the EP hit the "Enter" followed immediately by "Align" and choose your second star, say Polaris. "Enter" and the 'scope will slew automatically this time to Polaris. Just repeat the procedure to achieve alignment success.
Now for further reference, if you go into the CN home page, select "Articles" and then "Telescope Articles" you'll see I wrote treatise on the achievement of accurate tracking in Celestron 8is 8iSEs and 8SEs which in essence, states that when you view objects which are situated premeridian, use the Right and Down buttons for final centralisation after the GoTo slew and Right and Up when postmeridian. Please read the article if you wish.
This then should iron out a few of your problems Jase. As I said, I have only worked with 8" 'scopes of this series but in principle we should, by and large, be able to read across.
My apologies if you find you know all or most of this already. On the other hand I hope it will help you to less frustrating viewing. Please feel free to ask more if necessary.
Regards,
Tel
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Truth is the cubed root of Verbosity.
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JDSherman
super member
Reged: 04/19/06
Posts: 183
Loc: Central NJ, USA
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Hi folks I was wondering if I could get some help here. I am about to try to polar align my 8iSE on a (what I believe is a) Celestron Heavy Duty wedge. I checked mike's web site at http://www.nexstarsite.com/AlignmentFAQ.htm but I couldn't find a specific polar alignment procedure. I did find this on the web however - http://www.telescopereviews.com/documents/nexstar8i.pdf
The problem here is that the information from telescopereviews.com seems backwards as far as the legs of the mount go. Assuming that issue is due to the difference in the example wedge vs. my wedge, do I just point the mount arm towards celestial north (not magnetic north) and set the latitude on the wedge. After that I follow the instructions according to the controller. Does anyone have a preference on which EQ Align type is best? Also the procedure asks me to align the OTA to the meridian. Isn't it already aligned to the meridian if I start with the mount arm and the OTA pointed at the NCP?
Sorry for all of the questions. Any help is appreciated. Especially if it points out the reasons why the referenced PDF from telescopereviews.com seems backwards to me.
Thanks in advance for any help.
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Stellarvue 102ED (sn 0107)
NextStar 8i SE XLT
Astro Tech 66ED (Green) (sn 6680003)
Orion Atlas, AT Voyager
Denkmeier Powerswitch
3.2mm, 5mm BO/TMB Planetary, 7mm UWAN, 10mm Ultima, 16mm UWAN, 24mm Panoptic, 33mm SWAN, 40mm TMB Paragon
Orion Starshoot Pro
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MikeML
super member
Reged: 10/09/04
Posts: 197
Loc: NJ
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FWIW, I don't know if all Celestron bolt patterns are the same, but I have a heavy duty wedge on a Celestar tripod. With this setup one leg points due South when aligned.
Secondly when you have your scope mounted the fork should point at the pole
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Mike
CGE 1100
TV 85
FLT-110
Maxscope 40
Megrez 80, etc., etc.
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JDSherman
super member
Reged: 04/19/06
Posts: 183
Loc: Central NJ, USA
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Now that sounds like what I'm expecting to see. If you don't mind saying, where in NJ are you? I'm in East Windsor.
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Stellarvue 102ED (sn 0107)
NextStar 8i SE XLT
Astro Tech 66ED (Green) (sn 6680003)
Orion Atlas, AT Voyager
Denkmeier Powerswitch
3.2mm, 5mm BO/TMB Planetary, 7mm UWAN, 10mm Ultima, 16mm UWAN, 24mm Panoptic, 33mm SWAN, 40mm TMB Paragon
Orion Starshoot Pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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HI JD,
Does a Nexstar 8iSE actually fit on this heavy duty wedge ?
I was under the impression that these were only designed to carry the 8", 9.25" and 11" fork mounted 'scopes, not the single arm 6SE, 8i, 8iSE and 8SE series for which there is an appropriately designed alternative wedge available.
Regards,
Tel
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Truth is the cubed root of Verbosity.
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JDSherman
super member
Reged: 04/19/06
Posts: 183
Loc: Central NJ, USA
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I would say yes. The three bolt holes line up perfectly. The only issue I can see possibly being a problem (keep in mind I have not taken it outside yet) is that when I need to align the 90 degree OTA and arm marks the scope just touches the tray part of the wedge. I think it clears and if it doesen't I think I can finess it by moving the Ray's Bracket since it is VERY close if it indeed touches at all. Or I could just do surgery on the tray if necessary - but It looks OK by just eyeing it. I'll check it out for real if the clouds ever clear here in NJ.
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Stellarvue 102ED (sn 0107)
NextStar 8i SE XLT
Astro Tech 66ED (Green) (sn 6680003)
Orion Atlas, AT Voyager
Denkmeier Powerswitch
3.2mm, 5mm BO/TMB Planetary, 7mm UWAN, 10mm Ultima, 16mm UWAN, 24mm Panoptic, 33mm SWAN, 40mm TMB Paragon
Orion Starshoot Pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi JD,
Sounds OK and with a little modification should work fine but I must admit I don't understand why, as Mike commented, one leg of the tripod should point due south. North yes, towards the region of Polaris, but south only if you're in the southern hemisphere which clearly your're not.
In normally setting up a "tripoded" 'scope for polar alignment its usual to choose one leg to be known as the "north leg" for current and future orientation of the whole set up if the viewing position is not a permanent one.
Some people therefore take to marking an "N" on the chosen leg. I always guessed that the leg of our tripods carrying the Celestron logo on it was to be used for this purpose.
(NB. the foregoing of course describes for NH users like ourselves).
If this leg is then set to point north, then the other two legs must point east and west respectively.
I don't know the heavy duty wedge that well at all but I have a standard one for my N8i (Ray's Bracket et al.)and from my experience, find Anjal C. Sharma's documented orientation perfectly sound.
I can't see therefore that the design of the wedge itself would make any difference but I may be wrong so in my case it's :
Chosen leg to the north -- mount arm to the west.
I'm puzzled therefore, but then again I may well be missing something !
Best regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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JDSherman
super member
Reged: 04/19/06
Posts: 183
Loc: Central NJ, USA
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Tel,
From what I've seen in Anjal's doc and from what Mike posted above I think for us HD wedge users the bolt pattern is reversed. There is no other way to attach the HD wedge to the standard tripod without the (a) "pointing leg" pointing south for us. No big deal. Mount arm to the west you say. That is a clue I hadn't noticed.
Thanks for your help.
--------------------
Stellarvue 102ED (sn 0107)
NextStar 8i SE XLT
Astro Tech 66ED (Green) (sn 6680003)
Orion Atlas, AT Voyager
Denkmeier Powerswitch
3.2mm, 5mm BO/TMB Planetary, 7mm UWAN, 10mm Ultima, 16mm UWAN, 24mm Panoptic, 33mm SWAN, 40mm TMB Paragon
Orion Starshoot Pro
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JDSherman
super member
Reged: 04/19/06
Posts: 183
Loc: Central NJ, USA
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I posted this in the other thread but it fits here. I found another resource for polar alignment if anyone is interested: http://c8astronomy1.home.comcast.net/html/c8polar.htm
--------------------
Stellarvue 102ED (sn 0107)
NextStar 8i SE XLT
Astro Tech 66ED (Green) (sn 6680003)
Orion Atlas, AT Voyager
Denkmeier Powerswitch
3.2mm, 5mm BO/TMB Planetary, 7mm UWAN, 10mm Ultima, 16mm UWAN, 24mm Panoptic, 33mm SWAN, 40mm TMB Paragon
Orion Starshoot Pro
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osbourne one-nil
professor emeritus
Reged: 07/03/06
Posts: 710
Loc: Cumbria, England 54.5ºN 2.5ºW
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Perhaps I've missed this elsewhere, but is there any way of refining the alignment during a session? If it brings the intended target in slightly off centre, can you then update it? I know you can sync stuff for hard to find things, but is this the same thing?
Also, if I put some AA batteries in just in case I pull my power lead out, but never use them to pwer the scope, could I leave it turned on all the time so I don't have to keep putting the correct time in when I align? I don't have a watch you see. I'm too poor. I live in a shoebox.
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Celestron NexStar 6SE
http://www.greatasby.co.uk
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b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
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You can "update" alignments, when you get to an object, just hit "align" again and it'll guide you through the process.
As to the batteries, if you leave the power on with the AAs in, they'll end up discharged pretty quickly.
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"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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osbourne one-nil
professor emeritus
Reged: 07/03/06
Posts: 710
Loc: Cumbria, England 54.5ºN 2.5ºW
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Thanks...sounds fairly straightfoward! I just wondered with the batteries if they weren't being used to slew the scope, whether they'd last for weeks. I thought I was asking too much. I'll buy a watch.
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Celestron NexStar 6SE
http://www.greatasby.co.uk
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meanbean
newbie
Reged: 01/22/08
Posts: 4
Loc: Colchester, CT
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Hi everyone, I'm new to Cloudy Nights-and to my new 8SE. Do I have to do an alignment if I'm not going to use the GoTo feature? Will it still track properly?
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Skip
Starlifter Driver
Reged: 01/23/08
Posts: 1343
Loc: San Antonio, Texas, USA
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meanbean,
I have a 6SE but it uses the same mount and controls as the 8SE. Yes, if you want it to track you will have to do an alignment. You can aim it at an object and use the slew buttons to keep it on target, but that is very clumsy. The good news is - alignments are easy! I prefer the auto two star, but SkyAlign works pretty well too. I have used the solar system align when looking at Jupiter and the Moon, but if you are going to go for deep sky stuff, that's not very accurate.
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Skip
Celestron NexStar 6SE (Small Caliber)
Orion SkyQuest XT10i Intelliscope (Howitzer)
2 25mm Plossls; 24mm & 13mm Hyperions; 10mm Plossl; 6mm BO/TMB; 2X Barlow
Telrad + 4" Riser
7Ah PowerTank
Starbound Observing Chair
Eagle Eye Observatory, Texas -
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Skip
Starlifter Driver
Reged: 01/23/08
Posts: 1343
Loc: San Antonio, Texas, USA
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Oh, and welcome to CN. Great bunch of very helpful folks.
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Skip
Celestron NexStar 6SE (Small Caliber)
Orion SkyQuest XT10i Intelliscope (Howitzer)
2 25mm Plossls; 24mm & 13mm Hyperions; 10mm Plossl; 6mm BO/TMB; 2X Barlow
Telrad + 4" Riser
7Ah PowerTank
Starbound Observing Chair
Eagle Eye Observatory, Texas -
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meanbean
newbie
Reged: 01/22/08
Posts: 4
Loc: Colchester, CT
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Thank-you Skip for the welcome and for the info. Yes, the 2 star alignment has worked well and I have even used a 1 solar system align to view Saturn this week in the east and it seemed to track okay.
In reading through all the threads on this website I find it most informative and everyone really shares their experience and tips.
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b1gred
Enginerd
Reged: 04/01/04
Posts: 15711
Loc: Castle Rock, CO 6677' MSL
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Welcome meanbean!
A solar align works great if you have an accurate location entered and very accurately center the object.
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"Dark Skies & Great Viewing"
RandyR / W0RDR
GPS 9.25 XLT/Sky Align /FeatherTouch
TV85 w/FeatherTouch
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meanbean
newbie
Reged: 01/22/08
Posts: 4
Loc: Colchester, CT
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So noted, I will keep that in mind. Thank-you.
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Cenk
scholastic sledgehammer
Reged: 05/29/04
Posts: 796
Loc: South East England
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Here are my tips, from my own experience on a Nexstar 6SE.
1) Mount the OTA the correct way on the mount. Match up the markers on the mount. You know it is mounted right when the OTA is flush against the mount and not raised in any way.
2) Level your OTA. Use a spirit level on the centre of the mount. This is sufficient for alignment.
3) Set your coordinates or city within 50 miles. Make sure the time and date are as correct as possible. Noting that the date is in US format. I am 40 miles from London, choosing London works perfectly.
4) Use SkyAlign or Auto 2 Star. Use 25mm or 15mm eyepieces. Doesnt matter which objects you choose as long as they are a fair distance away from each other.
5) Center the object with your (correctly aligned) finderscope (or any other finder), hit enter. Then align with your eyepiece. The right/up and right/down didn't make any difference to me. Just align did the trick.
That's all. Oh apart from the Moon nearly blinded me in one eye !
Thanks.
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Celestron C8 Fastar on Nexstar 6SE/8SE mount
Revelation Binoviewers,2" Revelation Quartz Dielectric Diagonal
2 x Televue 32mm Plossls, 2 x Baader 8mm-24mm Zoom Eyepieces
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alser2
member
Reged: 02/23/08
Posts: 95
Loc: cork, ireland
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just wanted to thank you for that advice, i have google earth and never thought of doing that. i used the coordinates for my celestron the sky software. i use a firstscope 114 eq. literall y my firstscope. anyway thanks for that!
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Celestron Nexstar 6SE
Celestron Firstscope 114 EQ + Solar filter
Celestron 12x60 Skymaster Binos
4mm, 6.4mm, 32mm, 40mm Plossl, 2x barlow lens
10x, 20x, 25x celestron eyepiece
moon filter and various colour filters
seben LP filter
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alser2
member
Reged: 02/23/08
Posts: 95
Loc: cork, ireland
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hi all i was on a few monhs back about deciding on a nexstar 6 se, well i am glad to say i went for and i love it. the view of jupiter i got sunday morning at 430 am was well worth the lack of sleep!
i used google earth to get longitude and latitude, try downloading that. just find your address in it. it even has google sky within the application, for space exploring.get it!
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Celestron Nexstar 6SE
Celestron Firstscope 114 EQ + Solar filter
Celestron 12x60 Skymaster Binos
4mm, 6.4mm, 32mm, 40mm Plossl, 2x barlow lens
10x, 20x, 25x celestron eyepiece
moon filter and various colour filters
seben LP filter
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alser2
member
Reged: 02/23/08
Posts: 95
Loc: cork, ireland
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hi, if i want to get and use a solar filter for the nexstar 6se, how do i actually use the scope during the day. do i need the moon in the sky as well as the sun so as to do a solar system align? thanks
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Celestron Nexstar 6SE
Celestron Firstscope 114 EQ + Solar filter
Celestron 12x60 Skymaster Binos
4mm, 6.4mm, 32mm, 40mm Plossl, 2x barlow lens
10x, 20x, 25x celestron eyepiece
moon filter and various colour filters
seben LP filter
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Alan,
And if I haven't said so before, a warm welcome to CN.
In answer to your question, you do not need the Moon in the sky since you can align your 'scope directly on the Sun itself taking of course all precautions necessary to avoid looking directly at it through the 'scope or indeed through the finder. (I won't try to teach you how to suck eggs over that one) !
The mode of operation however is first to go into Utilities and page to "Sun Menu". Here you need to make sure that "Allow Sun" is selected otherwise at no time and as a safety precaution, will you be able to access the Sun.
Having "Allowed" the Sun onto the menu (solar system list), all you then need to perform is a standard solar system align.
I won't say that tracking is brilliant in this case and that a GoTo to nearby say, Venus or Mercury will be spot on in view of the fact you've aligned on one single, large target, but for solar viewing and imaging it works well.
I can't remember if the tracking rate moves automatically from the normal sidereal to solar rate but you can easily check that by going to the menu and accessing "Tracking".
If you need any further help please let us all know but hopefully this will put you right.
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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alser2
member
Reged: 02/23/08
Posts: 95
Loc: cork, ireland
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thanks tel, last time i was here i was asking about getting the celestron 6 se and i got great advice, and the advice never stops, what a great site! i will try what you say then, might as well ignore the finderscope so and just get the sun in the scope itself, thanks. i wouldnt expect tracking to work for mercury etc anyway, just wanted to get the sun up and running so to speak. over time i hope to improve my skill and the telescope's tracking and goto abilities.
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Celestron Nexstar 6SE
Celestron Firstscope 114 EQ + Solar filter
Celestron 12x60 Skymaster Binos
4mm, 6.4mm, 32mm, 40mm Plossl, 2x barlow lens
10x, 20x, 25x celestron eyepiece
moon filter and various colour filters
seben LP filter
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THEPLOUGH
Sir Ducksalot
Reged: 01/11/08
Posts: 6231
Loc: Carlisle, Cumbria, ENGLAND
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Alser2. If you look on the FORUM page at the top right hand side you will see an area marked POST. If you then go into that it will set you up with your own blank page on which to enter your own post... Not too say you can't post here but you have more chance of replies/answers if you start your own thread/topic..... HAS you can see by the title, this thread is about aligning scopes so not many people will be looking at it.... Hope this helps in pointing you in the right direction.. 
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Geoff...
Nexstar 8SE ...Plus bits & pieces
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Quote:
thanks tel, last time i was here i was asking about getting the celestron 6 se and i got great advice, and the advice never stops, what a great site! i will try what you say then, might as well ignore the finderscope so and just get the sun in the scope itself, thanks. i wouldnt expect tracking to work for mercury etc anyway, just wanted to get the sun up and running so to speak. over time i hope to improve my skill and the telescope's tracking and goto abilities.
Hi Alan,
Use of the finder, as you appreciate, is right out of the question unless you've got a filter fitted over the object lens. In any event the finder should be removed even if not used as the same heat is hitting it as would be directed at an unprotected main OTA. It will in all probability be damaged as a result of such unprotected exposure.
In my ignorance, I used to line up on the Sun by allowing its rays to enter the OTA and hit upon a white piece of card. I would then immediately slap on the filter, attach an EP, centralise all and get the alignment up and running. I subsequently learned that even a brief spell of unprotected heat can and will damage the 'scope. (In fact I should have read the manual more thoroughly) !
Nowadays therefore, I just point the OTA plus Sun filter and devoid of finder, in the general direction of the Sun and project the shadow onto my white card. With a little manipulation the Sun's image will appear somewhere in the EP. I then just centralise it and complete the "Solar System Align".
Best regards,
Tel
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Truth is the cubed root of Verbosity.
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alser2
member
Reged: 02/23/08
Posts: 95
Loc: cork, ireland
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thanks theplough, will keep that in mind for future posts. tel, good advice thanks, i will cover the finderscope with the cardboard box an eyepiece came in, it fits over it nicely. now all i need IS the solar filter, i'll get it soon.
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Celestron Nexstar 6SE
Celestron Firstscope 114 EQ + Solar filter
Celestron 12x60 Skymaster Binos
4mm, 6.4mm, 32mm, 40mm Plossl, 2x barlow lens
10x, 20x, 25x celestron eyepiece
moon filter and various colour filters
seben LP filter
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Tuco
journeyman
Reged: 04/23/08
Posts: 9
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Hi, my wife and I are new to this forum and new to astronomy (sort of). We just got a SE8 and expect it to arrive in about a week. We downloaded the manual and read it several times. This is a great site and this thread has been super informative. I still have a couple of questions about alignment:
1. Early in this thread someone mentioned that lattitude and longitude are not needed for the two star align. Should we enter this information anyway? Or does the scope not use it at all in this mode?
2. Im still trying to understand why the slew speed should be reversed on one of the directions. Also, they mention a recommended combination of slew directions when centering a star for alignment. This has to do with backlash and Im having trouble understanding how and why we need to do this. For example, if I overshoot using a recommended up motion, I have to use down to correct. So is the point that we need to go real slow and avoid overshooting when aligning?
I realize that these questions might be a bit early considering the SE8 hasnt arrived yet! But were pretty excited about learning all we can before our first use.
Thanks!
Jim
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Jim,
A very warm welcome to you and your wife to CN and congratulations on your choice of 'scope. This series certainly provides value for money in my opinion.
If you are prepared to take a little advice, then resist fiercely, the temptation to take the new 8SE outside immediately you've assembled it from the box otherwise I'm sure it will meet with initial frustration and disappointment. Assemble it of course, but in broad daylight and somewhere you can work on it to input all necessary data, adjust and refine the antibacklash etc. Any problems, the guys here are only a post away, so almost immediate help is at hand.
To this end and if you are not aware, the following website, designed by Mike Swanson is an excellent source of information.
www.nexstarsite.com/
I would also recommend you buy a copy of Mike's book, "The Nexstar User's Guide". A little dated these days, but still of great value.
Moving on to your specific questions,to be honest I've never considered making any type of alignment without having installed latitiude and longtitude as part of the initial hand control set up. It might well work (?): working on factory settings, which if you are not based in Torrance California, where they would have probably been set, they will not be applicable. Hence the need to set up in accordance with your specific location. If you do not know your Lat./Long., there is a "Nearest City" option but "Google Earth" will always provide !
Alternatively, you can simply try any one of the alignment procedures available without having entered your specific Lat./Long. (or nearest city) and see if it accepts. Remember though, resistance and meticulous setting up is better !
In answer to your second question, optional changes to the direction buttons apply only to the lower slew speeds (1 - 6 ). The reason for this option, is to take account (according to your wish) of the different orientation the image presents in the eyepiece according to which accessories are being used.
In all probability, you will never need to change anything but consider it as follows.
If as is normal practice, you will be using an eyepiece in combination with the diagonal , the image, presented to your eye will be upright but will be transposed horizontally (right will be left and left will be right).
Now take the diagonal away and view directly through the same EP. It will still be transposed horizontally but also inverted. Thus, for example, if you have a camera connected directly to the 'scope and you are guiding it, you may wish to reorientate the direction buttons rather than leaving them as is and getting your head around which way is up ! 
These settings have nothing to do with antibacklash per se but backlash does play a very significant roll in moving the object in the EP for both alignment and tracking. (I suggest we leave that one until you've got the 'scope).
Briefly though at this stage, there are prescribed ways of bringing an alignment star to the centre of the EP and also, for getting the best tracking depending on your chosen object's position in the sky.
Hope this helps for starters, Jim.
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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Tuco
journeyman
Reged: 04/23/08
Posts: 9
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Your reponse helped a lot. Thanks for the link, it has been added to our favorites list and should make some good reading this weekend. We purchased a couple of classic books a couple of weeks ago, the "Night Watch" book has been really helpful. Together with the planisphere and some binoculars, we have already found lots of stars and constelations. The process of finding stars to align the scope doesnt seem so complicated now. Is it just me or is a GPS option really unecessary for these scopes? If I can align this in just a few minutes without a GPS, then whats the point in having GPS? If so, Im glad we didnt spend the extra hundreds of dollars on a GPS model. (no need to answer this if it has been discussed in this or other threads, we will probably find these threads eventually!) Once we are up and running, we will likely come back with more alignment questions. Thanks again for the help. We look forward to eventually contributing answers along with our questions.
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Jim,
My opinion but one I know shared by many is that unless you envisage travelling about with your 'scope and I mean further than say a 70 miles radius of your home base, then a GPS is an unnecessary waste of money as I think you have concluded.
Even if you do travel further afield, there are at least two other options open to you. If you know where you are going and don't have access to say, "Google Earth", you can always note the Lat./Long. for the locations you intend to visit or alternatively, program in "Nearest City" when you get there !
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6590
Loc: Frederick Maryland
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I have a GPS unit on my 8i...have for years...it looks cool sitting on top (but the red power light has had a piece of electrical tape over it for years ..way too bright...
I LOVE the darn thing...it pulls down my current location (which btw) has not changes as much as 1/8 of an inch in the last 20 moinths, pulls in the correct time...and enters both into my scope brain....SAVES ME TIME...
Yep a 200 buck accessory that saves me oh about 3-4 seconds every single time I use it...
Worth the money ? ROTFLMAO ...not by a long shot..
BUT when I first purchased I kept my scope in the trunk of my car because I traveled, setting up in Say Pennsylvania on a Monday night and in Virginia oin Tuesday night ...the unit was a time saver because i never had to use a slow dial up connection from the el cheapo motels that the Company insisted I use to get my current location....
Another factor was that with the original 8i you had to both level the scope and point it North... The GPS unit
did both...level the scope and slew to North...that was nice .. so 200 bucks bought me an accessory that could find my current location, set the time, level the scope and point it North then it was able to do its dance and start the alignment process.... This actually was a good deal for me, in my situation...
Today I advise SAVE YOUR MONEY or better yet go out and spend the money on a GREAT Observing chair which you will get much more use out of and both your wallet and your feet/legs will thank you for...actually you eyes will thank you too as you can see so much more when you are relaxed and comfortable...
Oh and Tuco.... WELCOME to CN !
Bob G.
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CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
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 rick rian
The Lockster
Reged: 08/03/04
Posts: 21207
Loc: Upper Midwest
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Welcome aboard Tuco .. happy you decided to join the group!
I gotta agree with Tel and Bob G. above, I too would recommend saving the money and NOT buying the GPS unit. As Bob G. states, the 2 to 3 seconds it 'saves' isn't worth the price. I have the CN-16 GPS that I bought years ago when I purchased my NexStar 8i ... Back then (using the version 2 hand control) it used to level the OTA, point north and select the first alignment star with GPS align. It still works for date, time, location but if I were to have the choice today ... no way! There are so many other things to focus your spending, we can help with that too! 
Once again, welcome aboard!
--------------------
Rickster
NexStar 8i
TV85
Canon 15x50is Bins
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Anonymous
Unregistered
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Update...here is the location for Best Pair II.
http://www.ilanga.com/bestpair/
I tried one of the other sites and it came up not found, I I googled for the software and found this one.
Dave
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davecttr
super member
Reged: 07/20/08
Posts: 100
Loc: Medway, UK
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Do the alignment algorithms take into account any variation in the level of the scope? It seems to me that if you input accurate time and location, plus a good one star aligment then the goto and tracking should be good IF the scope is level. A one star alignment would only need to provide the direction of the celestial NP? If so, what extra accuracy does a 2 star align provide except a possible sky model adjustment for scope level? I reckon you would have to be pretty darn good to get spot on with levelling.
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'Wee Mak' Celestron 4SE
SkyWatcher 80mm f5 short tube
Orion StarBlast 4.5
Meade DSI 2 Pro CCD
-----------------------
If you have the wrong tool you need a BIGGER hammer.
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Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6590
Loc: Frederick Maryland
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Davecttr:
With Sky align level is honestly not important nor is what direction you actually point the scope ...when Celestron used North and Level as an alignment method (Meade still does) pointing the scope North and making it level WERE DARN IMPORTANT) as it was a true starting reference point...
Skyalign could care less which direction you point the OTA
BUT
If you level the scope your Goto's will be more accurate simply because you eliminated the small differences in the angle no matter if the scope slews to the North, South, East or West...
I use my built in level (eyeballs) and never have had problem)
When My 8i used the North and Level Method I used a GPS unit on the scope Which was calibrated to find true North PLUS was calibrated to level the OTA before the alignment procedure was started... so even then I never used a level...
Bob G,.
--------------------
CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Aaah!
As evident from my sig I have a 130 SLT and it has never, ever aligned properly despite my sincerest efforts. The constant message I get is "Align Success, StarPointer Off" even though my pointer is right on. Despite the Align Success, the telescope never hits a target dead on. It gets in the general area, but it always misses its target.
I've leveled it, aimed north, used a 15mm EP to center the stars, and still nothing. I've gone from Polaris to Antares (using two star align) to cover the most sky. This has gone on ever since I've owned this scope. Help?
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
There are two issues here: one of which I'm not too clear on.
In the first place, "Starpointer Off" merely means "Turn off the Starpointer" otherwise its battery will go flat !
As to the second point, in doing this, would you still have an alignment problem ?
It sounds from what you say, as if you would still have a problem irrespective of this "switching off" action.
If you can clarify this point and you do still have an alignment problem albeit your hand controller indicates success, please let us know so that we may help you further if necessary.
When, for example, you mention "never hits the target dead on" are you saying that the object is not visible in the eyepiece following a "GoTo" slew or that it's just not central in the EP?
Best Regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Wow, I never thought about "Starpointer Off" as meaning turn it off. (is it so hard for Celestron to add a Turn in front of Starpointer?) And since it isn't wired to the telescope then I'm sure it has no effect on slewing itself.
So yes, my HBX indicates success, but it fails anyway. Here's an example of what happens: Let's say I tell it to go to M13. It does its thing, and M13 is not in the EP, even at low power. I then kind of look through the pointer's window to get a hint of where the telescope is pointed, and it's in the right general area (in this case, the approximate area in the Keystone) but M13 is just not there.
Now, I have had very limited success (like, really limited). If I want to view a planet, like I've done with Jupiter, I'll do a planetary alignment on the planet I want to view and most of the time it comes back into the EP. About a third of the time the planet just grazes the bottom (although, in this case, I'm using a Barlow). The problem is, and I don't know if this can be helped because maybe the motors are just bad, that it drifts out of the FOV over time. Sometimes it's really noticeable, other times not.
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6590
Loc: Frederick Maryland
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Orenabah:
Lol...Do not worry about the starpointer ...I honestly would bet some serious money that most of us were confused with the message and scratched our heads...so welcome to the crowd...
Now I believe you scope uses Skyalign as its alignment method... so you definitely do not need to point it North anfd to be honest eyeball level is close enough...but in your situation I would advise you to actually level the tripod..
I am a big fan of Skyalign (just using 3 bright stars BUT doing a 2 star alignment is favored by most guys and gals..so lets go with the majority..and tell you to do a 2 star alignment...separate the two stars about 100-130 degrees apart...and since you mentioned Polaris ..why not use that star as your first star .....
Now center the first star in the eyepiece (higher power eyepiece the better)..but center it by defocusing it until it looks like a big donut ...when the donut is almost as bif as the FOV in the eyepiece it makes it very easy to accurately center the darn thing... press align then move on to your second star and repeat the process...
Since you said that the object drifted out of the FOV I'm curious what tracking rate you were using...solar,lunar, or sidereal??? use sidereal for everything except the moon...
Of course you have to enter the correct time and location..(hint for now use a near by city since its just easier to enter...
I am not sure how you change your time zone..on the slt 130 the default is Pacific Standard Time ...and I am not sure how you tell the scope that you are using Standard time or Daylight Savings time... (Menu- scope set up should
be the right place...
Try doing that as see if your GoTo's and tracking improve...
if not there are plenty of other things to set/change/ etc...lets just start with a few things most guys and gals do wrong initially...
Seriously it is not that hard. my 1st scope was the 114 GT and to be honest its goto's were in the ball park all night long (not dead center but within the FOV of a 25 mm eyepiece) but tracking was good for at least 1/2 hour...
Bob G.
--------------------
CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
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Cenk
scholastic sledgehammer
Reged: 05/29/04
Posts: 796
Loc: South East England
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Bob,
When do we centre and press "OK" and when do we press "Align". Could you clarify. I am still struggling with this part of the alignment procedure myself.
Thanks
--------------------
Celestron C8 Fastar on Nexstar 6SE/8SE mount
Revelation Binoviewers,2" Revelation Quartz Dielectric Diagonal
2 x Televue 32mm Plossls, 2 x Baader 8mm-24mm Zoom Eyepieces
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Bob, (Cenk).
Forgive Bob, for jumping in here but we get up earlier than you and since Cenk is on the same side of the water as I am, I thought he might be in a hurry to know the answer (providing I've understood his question and I get the answer right that is)! 
For what it's worth, this then is the way I align both stars when making my Auto Two star Alignment (or Two star Alignment).
(As you know, Bob, unlike you, I'm not a fan of "Skyalign")!
When I have aligned my chosen star in the finder, I move straight to the EP attached to the main OTA without pressing "Enter". I then manover the star to the centre of the EP and once centre is attained I press "Enter" followed immediately by pressing "Align". The same is repeated for the second alignment star.
If you can call it a tip, MY practice is actually to have a 20mm EP sitting in the OTA. I centralise the alignment star in the finder and then take a quick squint through the 20mm just to see that its there (somewhere in the FOV).
I then remove the 20mm relatively quickly and replace it with the finder 'scope crosshair EP (a 26mm in my case).
Finally I move the star onto the crosshairs of this EP and as said, press "Enter" and "Align" practically simultaneously. I then repeat the process with the second star.
Hoping this helps,Cenk,
Best regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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Pete GLA
super member
Reged: 12/20/07
Posts: 127
Loc: Windsor. South of Detroit MI
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Good morning Gang,
About the alignment procedure,
My understanding of the manual describing how to do a 1 and 2 and 3 star alignment is easy
Tel, Bob or anyone else...I usually do a Solar System alignment. But occasionally (when I'd like to stay out longer than 1 hour) I do a 3 star alignment.
This is where I think it DOES NOT matter how you Sky Align, since I haven't had a consistant streak of near central slewing to targets in this 1 year of having the 8SE and also I've the 114GT purchased when the Mars attack of 2003 occurred (but that I gave to my best friend to use)...
What I mean by "it doesn't matter" is that if you do as I always do, is going to your backyard, or friends house, or out in the county and having to set up, when you level the tripod, as you all well know, you never level the tripod exactly the same, (well because we're human). Tonight all targets are within a 200x EP, the next night only certain objects in specific area of the sky are in the FOV. And I truly believe that is because the tripod one night is levelled exactly, other times it is levelled but it is slightly elevated to the East, or to the West...
So when I know I've the target dead center and watch it for as long as a 1/2 hour there is a drift, whether N or S especially, and I think this is because the tripod isn't exactly levelled...
About performing the Sky Align, the 1st star to align I manually slew to the star and as stated in the manual, end with the same 2 arrows when centering all 3 stars, I move the star slightly behind center, meaning I allow the star to drift to center and then I press Align. I do this for all 3 stars...
So in conclusion, I see no right or wrong method of Sky Alignment, because You 1st NEED TO PROPERLY LEVEL THE TRIPOD... 
Anyone would like to confirm...correct...this point. Because I am perplexed about this simple procedure, yet very important... 
In progress of a beautiful week long sunny skies, but you know haze, contrails, neighbour's floodlights on, and so on...
Hoping Clear Skies In Your Neighbourhood,
Pete
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Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6590
Loc: Frederick Maryland
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Since I honesty do not do an alignment very much all I czn tell you is how I normally do it when I have to...
Like Tel I really do not follow the directions that the HC gives me... When it tells me to center the object in the Viewfinder
I just glance and make sure I can see the object in the 42 mm EP that I store in my scope all the time... and hit enter at that point ..I do not even take the time to center the object in the viewfinder ... .then I hit the rate key out of habit and set it to 3 or 4 and center the object in the eyepiece not even bothering to use any specific direction keys...I then defocus the object to get a nice big donut and center it BUT this time only use the right and down buttons ..if I screw up I just move the object off center and start again...and only use the right and down buttons...
That's how I do it... very much the same procedure as Tel uses but I normally do not switch the 42 mm EP to a higher powered one (unless I'm in the mood to be anal) and do not use a cross hair EP to center the object I just defocus...
The last 5-6 times I had to align a scope it was with my CPC and I use the same method with it..as I described above . except I do not store an EP in the OTA so I actually
do not use the 42 mm EP ...usually I grab my 26 mm 70 degree FOV EP and use it...
Bob G.
--------------------
CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
|
orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Quote:
Orenabah:
Lol...Do not worry about the starpointer ...I honestly would bet some serious money that most of us were confused with the message and scratched our heads...so welcome to the crowd...
Now I believe you scope uses Skyalign as its alignment method... so you definitely do not need to point it North anfd to be honest eyeball level is close enough...but in your situation I would advise you to actually level the tripod..
I am a big fan of Skyalign (just using 3 bright stars BUT doing a 2 star alignment is favored by most guys and gals..so lets go with the majority..and tell you to do a 2 star alignment...separate the two stars about 100-130 degrees apart...and since you mentioned Polaris ..why not use that star as your first star .....
Now center the first star in the eyepiece (higher power eyepiece the better)..but center it by defocusing it until it looks like a big donut ...when the donut is almost as bif as the FOV in the eyepiece it makes it very easy to accurately center the darn thing... press align then move on to your second star and repeat the process...
Since you said that the object drifted out of the FOV I'm curious what tracking rate you were using...solar,lunar, or sidereal??? use sidereal for everything except the moon...
Of course you have to enter the correct time and location..(hint for now use a near by city since its just easier to enter...
I am not sure how you change your time zone..on the slt 130 the default is Pacific Standard Time ...and I am not sure how you tell the scope that you are using Standard time or Daylight Savings time... (Menu- scope set up should
be the right place...
Try doing that as see if your GoTo's and tracking improve...
if not there are plenty of other things to set/change/ etc...lets just start with a few things most guys and gals do wrong initially...
Seriously it is not that hard. my 1st scope was the 114 GT and to be honest its goto's were in the ball park all night long (not dead center but within the FOV of a 25 mm eyepiece) but tracking was good for at least 1/2 hour...
Bob G.
Whenever I start an alignment it prompts me for the time and date and all that. It remembers timezone and latitude/longitude which I looked up on Google Earth or something.
When I aim at a planet, like I have been with Jupiter lately, I do a solar system align, and align on the planet I want. It does drift out of the FOV slowly, and when I'm imaging for some reason its more obvious than just by eye. Maybe that's just because I bumped the scope, even if it was just vibrations from changing eyepiece to camera?
The best luck I've ever had with DSOs was one time M13 just barely grazed my eyepiece (the bottom edge was in the FOV). Granted, I can find most of my targets without the help of an alignment, but I would like to start shooting some short subs and a poor alignment doesn't help.
I've always used 2 star align when I try these. I've tried SkyAlign a few times but I always figured that telling the scope what stars it was looking at would give it a better idea of what my sky looked like.
Pretty much, here's what I do when I try a 2 star align:
I eyeball the scope's little built in level. It's on fairly flat ground to the extent of my knowledge so I go with that.
I then level the OTA. I don't know if that helps or not, it just kinda felt right when I thought of it. I enter the date and time and tell it to first go to Polaris. At this time I've got a low power EP in. This is for the "Center Polaris" step - I switch to something like a 15mm EP, and for the record I don't focus it, and I center it in there.
I then tell it that star #2 is Antares, and then I slew there and repeat everything with the EPs and centering.
Then I tell it to go to M8. The scope will miss, but if I nudge it a bit here and there M8 will be in the general area, just not in the FOV.
Sometimes I trade Antares for Arcturus, or Vega when it was a little lower in the sky. Still doesn't help.
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
I don't know what the other folks here think, but from what you are saying, it seems to me that your alignments and subsequent "GoTos" are pretty "Hit and Miss" and mainly "Miss" by all accounts.
Maybe we ought to be addressing the problem(s) by going back to basics which at least draws the starting line once more.
With this in mind therefore, my first question would be to ask you how long have you had this 'scope ?
My second would be to ask whether you've made a "Setup Scope" according to the hand controller "Menu". (This involves setting your GoTo Approach, Slew and Filter Limits and Antibacklash etc.). Have you covered all of these aspects ?
Thirdly, and assuming the above have been set correctly, are you absolutely convinced that your Lat./Long., time, date and time zone are all entered correctly each time ?
Im probably stating the obvious, and if so, I apologise, but I always feel that it's best to know the name of the game before playing.
Could you please advise on these initial "necessaries" ?
Best Regards,
Tel
BTW. As a footnote (and afterthought!) but of great importance : what are you using as a source of power for your 'scope ?
--------------------
Truth is the cubed root of Verbosity.
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Quote:
So in conclusion, I see no right or wrong method of Sky Alignment, because You 1st NEED TO PROPERLY LEVEL THE TRIPOD...
Anyone would like to confirm...correct...this point. Because I am perplexed about this simple procedure, yet very important...
Pete
Hi Pete,
My impression is that inaccurate tripod levelling can affect Skyalign, but since I personally never use it, I cannot comment with any reliabilty.
However, if you're familiar with Mike Swanson's excellent book entitiled "The Nexstar User's Guide" and indeed have a copy, take a look at pages 84 and 85 on which he describes "Alignment Myths".
The second "Myth" on his list, is specific to tripod levelling.
The book is a little dated now but most of its content is as relevant today as it was when first published.
If you cannot access the text, let me know.
Best regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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Pete GLA
super member
Reged: 12/20/07
Posts: 127
Loc: Windsor. South of Detroit MI
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Good Morning Tel,
My comment was for Orenabah to aid him (hopefully) in his dilemma.
What I could've added was to use a larger bulls eye level, since the supplied/bought smaller one makes it more difficult to level. But by what our gang has stated, properly levelling the tripod isn't that importatnt as long as it is reasonably levelled.
Maybe what Orenabah's 'scope has is an error in the software?
I had the 114GT, and almost every time out, I had to do > 2 Sky Align attempts to get the 'scope working right.
Most of the failed attempts were "Alignment Failure".
Hoping Clear Skies In Your Neighbourhood,
Pete
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Pete GLA
super member
Reged: 12/20/07
Posts: 127
Loc: Windsor. South of Detroit MI
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Almost forgot,
Tel I don't have Micheal Swanson's book...
Pete
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Quote:
Hi Orenabah,
I don't know what the other folks here think, but from what you are saying, it seems to me that your alignments and subsequent "GoTos" are pretty "Hit and Miss" and mainly "Miss" by all accounts.
Maybe we ought to be addressing the problem(s) by going back to basics which at least draws the starting line once more.
With this in mind therefore, my first question would be to ask you how long have you had this 'scope ?
My second would be to ask whether you've made a "Setup Scope" according to the hand controller "Menu". (This involves setting your GoTo Approach, Slew and Filter Limits and Antibacklash etc.). Have you covered all of these aspects ?
Thirdly, and assuming the above have been set correctly, are you absolutely convinced that your Lat./Long., time, date and time zone are all entered correctly each time ?
Im probably stating the obvious, and if so, I apologise, but I always feel that it's best to know the name of the game before playing.
Could you please advise on these initial "necessaries" ?
Best Regards,
Tel
BTW. As a footnote (and afterthought!) but of great importance : what are you using as a source of power for your 'scope ?
1. I've had this scope since uh, December 24th, 2007.
2. Uhm, no. I wasn't really aware that this existed.
3. I got my coordinates off of Google Earth like right on top of my house. I set the time from my watch which is more or less on atomic time (just because at work they have atomic clocks and my watch is fairly well in sync with them)
I guess the problem is number 2. --what's in there that I should look to change?
And as for my power I'm using a Powertank.
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
|
Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Quote:
Almost forgot,
Tel I don't have Micheal Swanson's book...
Pete
Hi Pete and a Good evening to you !
If you're interested, here's the paragraph from "The Nexstar User's Guide".
Quote :
" Myth 2 . You must accurately level the tripod.
It is true that a carefully levelled tripod is necessary if you want to use GPS or Auto Alignment to accurately point at the two alignment stars. It is also true that an unlevelled tripod will sightly affect the Filter and Slew Limits by tilting their frame of reference. But other than that, levelling the tripod has no effect on GoTo accuracy. To test this, I set up my N80 with the tripod about 15 degrees off level. I then performed an Auto Alignment, being careful to centre the correct stars. After the alignment completed, GoTo and tracking performed normally. Consider the fact that no matter what angle you tilt the tripod to, there is somewhere on Earth where it would be level."
Unquote.
The book is as said, slightly dated now, indicating that within our series of 'scopes, the N8i and N5i were the current models.
More up-to-date information can be obtained from Mike Swanson's website under www.nexstarsite.com if you are not already aware of this.
As to Orenabah's misalignments, from his recent posting, the problem seem to be more complex than first thought although I'm sure not insuperable.
Hoping this helps,
Best Regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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Pete GLA
super member
Reged: 12/20/07
Posts: 127
Loc: Windsor. South of Detroit MI
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Good Evening To You Tel,
1st - Where is the quote button to make it easier?
Quote from Mike Swanson's book:
"To test this, I set up my N80 with the tripod about 15 degrees off level. I then performed an Auto Alignment, being careful to centre the correct stars. After the alignment completed, GoTo and tracking performed normally. Consider the fact that no matter what angle you tilt the tripod to, there is somewhere on Earth where it would be level."
Given this fact, (I should try this for myself) so my concern as to why some nights are more precise slewing to targets than others, would be the choice of 1, 2, or 3 star alignments, since I use different stars, (not every night I observe at the same time). So because of trees being in the way, I have to use different stars to do Star Align...So this may be the reason of not having consitantly targets near center of FOV...
Thanks Tel for the info
Now to the #2 question you asked Orenabah, Set-up scope...
Would you think that instead of using the 130slt model he may have typed 80slt model
Because, now that it came to mind, I mistakenly entered the wrong scope model, and when I had the scope slew to a target, it was a consistant 15 degrees off!!!
So I went back to set-up scope and indeed I had entered the wrong scope model...
Maybe this could be the reason?
Hoping Clear Skies To Your Neighbourhod,
Pete
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Pete,
Sorry you've lost me, or perhaps I'm just not thinking straight, but where / how would I type in the model type ?
Best regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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Pete GLA
super member
Reged: 12/20/07
Posts: 127
Loc: Windsor. South of Detroit MI
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Hi Tel,
I had the 114GT model which as you know was replaced by the 130SLT, and if I understood you correctly, under "setup scope" there's Setup Time-Site, Anti-backlash, Slew/Filter Limits, Direction Buttons and finally Select Model. Under Select Model, you have a choice of entering which Model Scope you'd want to use. Whether it's the 80GT or 114GT. So I'm assuming that the SLT models have that same function...
So if you mount the 114GT scope on the tripod and under Select Model, you enter the 80GT, computer would GoTo and track thinking there's an 80GT scope mounted. I don't know why of the inaccuracy of slewing to a target. But maybe because of the difference in diameters of the scope I would think.
Therefore, that is what I'm thinking Orenabah might have under the Setup scope-Select Model...
Hope that this will clear the air in my understanding/thoughts of Orenabah's predictament.
Pete
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Pete,
I'm very sorry but I'm still confused.
Perhaps it was necessary to input a model name, (Select Model), with the older 114GT, (which I think you'll find is now replaced directly by the 114SLT), but having looked through the 130SLT manual, I personally can't find any reference to the need to do this with this model.
Nor in fact would I expect to do so because surely, it's the mount that controls the 'scope and the mount and hand controller are the same throughout the SLT series as far as I'm aware.
(Isn't that so) ?
I still think therefore, that Orenabah's problem lies, to a large extent, in a lack of initial 'scope preparation which needs to be addressed, otherwise there are so many, perhaps too many variables here to contemplate why his 'scope's off target.
Best regards,
Tel
--------------------
Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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To my surprise here there is no "Select Model" option under Set Up Scope. However, under the Utilities Menu, under Version, I got this:
HC: SLT 4.12
MC: 5.09 5.09
NexStar SLT
No specific make or model in there.
But I do think I might have found my problem. Messing around under Set Up Scope, in TrackMode found it to be set to "Off". I'm guessing it should be on Alt-Az.
There was also this option called "Calibrate GoTo" that caught my eye, any ideas on what use this is?
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Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
What you have identified there is the handcontrol version. HC = Hand Controller (Version 4-12 -- same as mine in fact) and, MC = Motor Control. Mine also identifies itself (in my case as "Series i"), because it is a Nexstar 8i.
It could have, for example, been a 5i so "i" is all encompassing as being part of that range of 'scopes. (Supseded now by the SE series).
I'm afraid you haven't found the solution to the problem from what you say about the tracking being "Off". It remains "Off" by default until the chosen alignment procedure is complete, Thereafter it defaults to sidereal tracking but gives options for solar and lunar tracking. You may also, if you wish, turn it off, although I can't imagine why anyone should want to do so when the 'scope is up and running.
As to calibrate GoTo, this is in essence just to optimise the best performance according to the weight of attachments and the balance of the 'scope. It won't help you through your current problem though.
If you are happy to let me do so, I will willingly try to help you through the procedures for initially setting up your 'scope tomorrow sometime if I can, but as this is a little involved and it's past midnight here in the UK, I'd prefer to leave it until then. In the meantime I strongly advise you to read the section on "Scope Set-Up " and "Utilities" in your manual. If you don't have one, then it can be downloaded as follows.
http://www.celestron.com/c2/images/files/downloads/Nexstar_SLT_manual.pdf
Hope this helps,
Tel
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Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Thanks for all your help. I really appreciate it.
I'd love the help on setting it up, if it's not too much trouble. Let me, however, double check my coordinates (I just grabbed them off of heavens-above). If they're off I will never, ever, forgive myself.
To the best of my recollection, when I initially set up this scope it was sort of just a "turn it on, okay, try alignment, *gets coordinates off google earth* enter time, okay, try align..ahh!"
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Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
Let me say firstly, that I don't own a 130SLT but a Nexstar 8i. However, the "setting up" should be exactly the same. Thus said, all these settings can be made indoors in daylight.
Accepting you're satisfied that you've entered your Long./ Lat. co-ordinates correctly, and your power source is well charged, proceed as follows.
1. Take a look at the OTA in the mount arm and ask yourself whether it looks well balanced. Better still, take it off of the arm, lay it on a soft flat surface and find its centre of gravity.
Bob G. has the ideal method to accomplish this by resting the OTA on a pencil and then moving the OTA back and forth upon it until reasonable balance is achieved. Once this balance point is found, mark it on the tube and then replace it in the dovetail such that the mark aligns with the dovetail's centre. The OTA will now be well balanced on the arm which in turn, will put less strain on the drive motors and assist GoTo accuracy.
2. Switch on the 'scope. Press "Menu".
"Tracking" should appear on the LCD screen. (if not, toggle on the "6" or "9" buttons of the control panel until "Tracking" does appear).
With "Tracking" now on screen,Press "Enter". "Mode" should now appear. Press "Enter" to see "Off".
Now using either the "6" or the "9" once again, page up or down where the "Mode" options will be displayed.
These will be : Alt/Az. : EQ North : EQ South : Off :
Choose "Alt/Az." and "Enter" followed by "Undo".
This operation sets the mode of tracking and, when eventually aligned, will provide a sidereal tracking rate (by default). This can be manually varied according to solar or lunar viewing but at this time this is of no consequence.
3) Having pressed "Undo" you should now see Tracking" once more on the LCD. Now toggle either the "6" or the 9" button until "Scope Setup" appears. Press "Enter" to see "Set Up Time Site". Press "Enter" again.
You should now see "Enter Longitude". Check that your figure is correct. If so, press "Enter". You will now be asked to confirm "West" or "East". If, for example, you are in the US then confirm West. If in mainland Europe, "East". Use the "6" or "9" to toggle between the two. Assuming "West" appears and you're in the US, press "Enter".
You are now asked to enter / confirm your latitude. Assuming your figure to be correct, press "Enter" whereupon "North" (or "South") will be displayed. Toggle "6" or "9" once again to the direction appropriate to your latitude, (ie. North America will obviously demand a "North" confirmation) and then press "Enter".
A request for you to enter the appropriate time is now displayed, Skip any relevant entry at this stage because any time entered is only applicable when you come to align under the stars.
Press "Enter" to see "Standard Time". Using the "6" or the "9" decide on whether you want to retain "Standard Time" or the altenative, "Daylight Saving". Once you decide, press "Enter".
You will now see "Select Time Zone" displayed. My 'scope is set to "Universal Time" because I live 1 deg. West of the Meridian line but say you live in NY, then I guess your time zone will be -5 (Check !). Select therefore and press "Enter".
You will now see the date appear. Again, skip this for the moment because it has no relevance until you are aligning your 'scope outside. Press "Enter" therefore, whatever date is displayed. This should take you back to "Scope Setup -- Set Up Time Site".
4. Using "6" or "9" toggle until you reach "Slew Limits" and then press "Enter". Set the "Slew Alt. Max. to a figure appropriate to the number of estimated degrees your OTA will elevate to before striking the base. For example, my Nexstar 8i will pass comfortably above the base of the mount so I set to 90 degrees but if your OTA cannot avoid striking the base, set the figure to what you think is appropriate to avoid this safely. Press "Enter". Now set the "Slew Alt Min to "+00" degs. Press "Enter" followed by "Undo".
5. By similar token, toggle again to find "Filter Limits". Press "Enter". This setting allows the OTA to avoid GoTos to objects below your horizon, (out of sight), while preventing as with the "Slew Limits", the OTA from hitting the base of the mount.
You should now see "List Alt Max. Set this to the same figure you chose for your "Slew Alt. Max." Press "Enter". Again, as with the "Slew Limit " setting, set "List Alt Min. to "+00". Now press "Undo" (several times?) to return to "Scope Set Up".
6. Toggle as usual until you obtain "GoTo Approach" on screen and press "Enter". With "Azm Approach" on the LCD, press "Enter" and make sure of a "Positive" setting. Press "Enter" once again. Now toggle to obtain "Alt Approach" on screen. Set this to "Negative" and then press "Enter" once again. ("Alt Approach" settings should be experimented with in the field to assess the better one (positive or negative) but for now, "Negative" will suffice. Note that for Northern Hemisphere users, the "Azm Approach" setting must be positive, while for Southern Hemisphere users, it must be negative. Press now "Undo" (several times) to return to "Nexstar Ready".
There are one or two features still outstanding at this stage, noteably the all important antibacklash settings, but I would like to deal with this separately once you're happy with what we have discussed here and have actioned all the information.
If I have made any mistakes in this text, please forgive me but as you can see it is quite involved !
Let me know therefore if you still have any problems at this set up stage or are ready to move on to the next set of instructions.
And if in doubt, don't forget to consult that manual !
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Wow...thanks so much. I'm going to go try this now.
I suppose it can't hurt to ask, although I guess it's best to expect a myriad of opinions here...what's the best alignment option?
Edit - I've done all of what you outlined above. The only major change was a slight position change in the dovetail. The only other real change was a longitude change (in seconds, that's not a big deal anyway)
I don't know if you have anything else up your sleeve as of right now. I'm waiting for the sky to get dark enough to align with.
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
Edited by orenabah (09/23/08 07:03 PM)
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
I'm sorry I missed your last posting (above) but I guess by the time it arrived I must have been trying to catch up with some sleep. !
I hope you had more success last night but as I mentioned as an attachment to Ernie00's posting, you should refine your settings a little further, taking into account the need for good antibacklash settings and alignment practice.
Perhaps though and before we resume (if you wish), on these addition refinements, you could give us a detailed report on how it went last night ?
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Last night was..ahh..depressing. The cause may have been a lack of being level but, as has been stated in here, that doesn't really matter?
I followed everyone's advice, with the finding center of gravity, etc. I did a SkyAlign on Polaris, Arcturus, and Altair in that order, centering with a lowpower EP and aligning with a 9mm EP and a defocused donut. This one outright failed.
I tried an Auto Two Star Align, using Polaris. The scope then tried to swing to Arcturus but was roughly 10 degrees off. This one, although saying "Align Success" failed to locate anything.
Then I tried a Two Star Align, using the same stars. Same result as with an Auto Two Star.
I'm on the verge of just giving up and finding a new mount for this. I don't think this is a matter of weight or being level. I think there's just a problem with the mount.
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Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
In view of last night's failures to align, I think it certainly might help us all, if you could try and detail, step by step, your last night's Auto Two Star Alignment through each stage, exactly as you performed it starting from the point you switched on the 'scope.
Forget for the time being the Skyalign and the Two Star Align attempts because it's much easier to concentrate on one procedure at any one time.
I choose this one because some users (including myself) have mixed feelings regarding Skyalign while Auto Two Star Align is basically just an automated version of Two Star Align.
In addition, Could you also provide details of your lat./long. co-ordinates, your chosen time zone and whether you are using daytime savings or standard time settings ?
Hoping we may yet solve this problem,
Best regards
Tel
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Truth is the cubed root of Verbosity.
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Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6590
Loc: Frederick Maryland
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I hate to say this BUT I personally have NOT heard of a single defective mount other then a mechanical defect...and even those are rare...... So I honestly believe you are just not entering the correct information in the correct format or are not doing something right...
Give us your location..(like a close by city...)
What time zone have you set the scope in...
What do you now have your goto approaches set at
What are you using to power the scope
How do you enter the time... (format 12 or 24 H ? using DST or standard time?
What direction buttons do you use for the final centering etc...
Maybe it time that a Moderator broke this thread out of the tips discussion and mad eit a stand alone thread ...That would reallly help...
GREG....TAKE THE HINT...Please
I know Tel is a little confused and I'm in the same boat...
Bob G.
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CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Thanks Bob,
Good idea !
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Auto Two Star Align:
I turned on the scope. I pushed Enter to select Auto Two Star Align. It asked me for the time (24 hour) and I input 20:21:something. (now that I think of it the error might have been me typing 8:21...I'm not aroudn the scope now so I'll have to check later). It then asked for the date which I put in (I'm skipping lat/long here) then asked me for a star. I selected Polaris and slewed to it. In my 25mm EP I centered it, and pushed Enter. Then in a 9mm EP, not focusing to make that donut, I centered it again and pushed Align. The scope then asked for another star. The first option was Arcturus and that was an easy find so I pushed Enter. It slewed, or tried to, and ended up about 10 degrees under Arcturus. The object is to center the thing, so I slewed until it was centered in my 9mm EP and said okay. The handbox then said Align Success. I told it to go to M3. No luck. I told it to go to M13. No luck. I have a high treeline so those were the only two I could pull off the top of my head that weren't behind trees.
BobG:
I'm close to New York City, as in about an hour away by train. I get my coordinates off of Google Earth which I don't have offhand on this computer, but I'll give you my coordinates that heavens-above uses, although it's kind of weird because it uses some decimal system instead of degrees, minutes and seconds:
41.21862 N, -73.44734 W
The scope is set to Eastern USA, and in Daylight Savings.
GoTo approaches are positive for azimuth and negative for altitude.
Power is, and has always been provided by a Power Tank.
As stated above I am using 24 hour time, daylight savings.
And for the final centering I can't really say. It's kinda weird, with up and down being inverted and left/right being regular. So I guess that usually I have to push "Up" and "Right" to get the star to move down and right, because it's usually to the top left when I switch EPs.
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
It would indeed make an enormous difference and lead to a failed alignment, of that I'm certain, so I can't imagine you inputted (as per your doubt), 08 21 00, rather than 20 21 00 because:
a) you would be prompted to confirm "am" or "pm" and surely remember doing so.
b) I'm pretty sure Arcturus would not be in your morning sky at this time. In any event though, please do as you intend, and check that no error was made !
On the topic of the direction buttons, HC reverse logic may be applied. In other words, the direction buttons can be set to your individual requirements. The manual however, tells you the mechanism of this change is to be found under "Utilities" but I think this is an error because the "Menu Tree" (in the same manual), indicates its place under "Scope Setup".
In any case you will find easily enough under one or the other and can thus adjust the slew directions according to your wish. Whatever you select, the alignment star(s) should be moved to the EP's centre with a final "Up" and "Right" movement when the GoTo Approach is (as recommended) set to " Alt. Negative".
All this being so or in need of adjustment, I'm still at a loss as to why, when the HC indicates " Alignment Success", this is still far from the truth.
When the 'scope slewed to the second star (Arcturus), can I take it that you gauged it to be 10^ off by the position of the red dot from the finder and from that adjusted the OTA to bring the red dot to cover Arcturus and thus appear in the 25mm EP ?
Your co-ordinates place you between Stanford and Bridgeport. Can we also assume that this is about right ?
(For info. the decimal figures you provided, convert to 41^ 13' 07" N /-73^ 26' 36" W. This format will be recognised by Google Earth).
I can't help thinking that this may well relate to the usual problems associated with place, time, and zone entries, but again, if you could supply this further information it might just help a little further in getting to grips with this. Meantime I'll give it some more thought.
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Greg,
As Bob suggested. perhaps it is high time to make this one a stand alone thread ? ?
It seems to me to be becoming more of a protracted problem solving exercise rather than offering any tips and thus is perhaps detracting from the purpose of this particular thread ? ?
Best regards,
Tel
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Truth is the cubed root of Verbosity.
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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I had considered the fact about Arcturus not being in the sky. Another consideration might be that I moved past the hour digits (say they were at 19, I might not have changed to 20) but I doubt that.
You are right about my location - and your coordinates are pretty spot on as well as I have just checked in Google Earth.
As for the scope's slewing to Arcturus that's exactly what I did. The scope had the azimuth pretty much right, just not the altitude.
If you'd like I can bring my camera outside with me tonight and take a series of photographs of what I do and what happens. Maybe that would help illustrate the problem?
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Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenabah,
Photography might indeed help. At least there's nothing to be lost and perhaps something to be gained.
What you might also try at this stage is adjusting your time site to Universal Time. In other words proceed with Auto Two Star Align to the point where you have to enter current Eastern USA Time but come forward by 4 hours. (This is the CURRENT Time zone offset relative to Universal Time).
So, if your local time when you set up is 19:30h., input 23:30. (Don't forget that if you set up after 20:00 h local time, you will not only have to input 00:00 for midnight or beyond, but also change to tomorrow's date).
Having entered Universal Time into your HC, you WILL need to toggle through the time zones from your existing Eastern USA time (ie. Zone -5) to produce Universal Time on the LCD. Once there, confirm it by pressing "Enter". You will now be on UT.
Don't worry that the time is out of "sync" with your local time. The stars have no appreciation whatsoever for earthly time or time zones. These are purely constructed by mankind to make life here easier !
This is at least the theory.
I have to admit that I have never done it myself by way of the fact I live only 1^ West of London and hence on the UT meridian so there is, for me, absolutely no need.
I do know though, that one of our CN colleagues, Randy R. sets to UT for his C9.25, and he lives in Colorado !
Give it a try, perhaps ? It might level the playing field a little !
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Morning thoughts.
I take it that the altitude axis itself is not too loose as to produce varying and erroneous slews and that the azimuth axis has zero to a very minimum amount of play in it if you attempt to turn it. (Gently! by hand just to feel for any backlash).
As to physically testing the altitude axis, does it feel at all loose when moved up and down by hand ? (All power off).
Alternatively, try elevating it under power, as high as it will go and then under slew rate 9, bringing it smartly down again to the horizontal. With your hand poised to catch the OTA should it drop, release the direction button.
Does it stop immediately ?
What do you think ?
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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atnbirdie
super member
Reged: 12/10/06
Posts: 118
Loc: Middletown, MD
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Orenabah,
With respect to the final approach issue, the bottom line is that you want to ensure you move the scope using the same final approach as it uses when it slews. Just look through the eyepiece as it is doing its final slew and not the directions objects are moving. In my scope that is down and right. You just need to push whichever buttons will make your scope use the same final movements as your scope does.
Steve
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Steve
Orionis Observatory (ExploraDome)
CPC1100 XLT; NexStar 8SE; Orion ST-80
-Denkmeier S-1 Shorty Power/Filter Switch
-FeatherTouch Microfocuser
-Gerbing Heated Motorcycle Clothes (a.k.a., Mobile Warm Room)
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orenabah
sage
Reged: 05/21/08
Posts: 291
Loc: Connecticut
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Hi guys,
First let me address a quick problem-the astronomer's scourge (clouds) has taken up residence over my head since last night and should persist to at least tonight making any alignment attempts impossible.
When I do get a clear sky again, I'll try setting to UT.
As for the alt-az axes, I can tell you right offhand. My altitude axis moves if I apply a slight force, both up and down. It has always done so. My azimuth, on the other hand, does not. Applying the same force to the azimuth like on the altitude just nets a slight jerking motion like it's locked in place. In other words, I can't move the azimuth axis without the handbox. I don't know if being able to move the altitude axis qualifies as being loose. It certainly does not drop to any extreme - it holds its position. So I can move it to say a 45^ angle and it won't drop to like a 30^. It's not that loose.
I'll try your test idea this afternoon as I'm not around my scope at this time.
atnbirdie- Mine also follows down and right now that I think about it. I'll keep that in mind when I go out next time.
--------------------
Paul S.
SLT alt-az mount & EQ4
Orion 8" OTA
Orion Apex 127mm Mak-Cass
Coronado PST
DMK21AU.04
Meade DSI pro
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Orenebah,
If your Goto Approach is set to "Alt. Negative", the alignment star (itself) needs to be moved "Up" and "Right" to centre it in the EP.
If you change the setting to "Alt Positive" then the star itself must be moved "Down" and "Right" to centre.
As to the tightness of the altitude axis and the response from the azimuth axis, it sounds as if all is OK.
Best regards,
Tel
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Truth is the cubed root of Verbosity.
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Radim
member
Reged: 11/06/05
Posts: 73
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Hi Tel,
why it is so important bringing into EP with right,up or left,down direction? I thought it does not matter which way it is centered ......
Thanks
Radim
Edited by Radim (09/28/08 07:23 PM)
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Radim,
I think by now there are some myths and legends atached to this aspect nowadays but still mixed with a lot of fact. The reason being that since the original concept of the Nexstar series , models have moved on.
Laying the groundwork, selection of a positive or negative GoTo approach setting determines the final movement of the OTA in approaching the object while minimising the backlash inherent in the spur gear drive of this series of 'scopes.
For Northern Hemisphere users, the GoTo approach must always be set to positive, (last movement to the right), while the opposite is true for the Southern Hemisphere. The choice therefore is in the altitude setting.
With a positive altitude approach setting, the OTA will be seen to move upward to the object when making the "final run", while if set to negative, the OTA will move downwards onto its target. A negative approach is the default setting.
Now for the mixed myth, legend and truth !
When Mike Swanson, argueably the guru of Nexstar 'scopes, wrote and published his excellent book covering the range, this particular series had progessed from the Nexstar 5 and Nexstar 8 to the "i" versions both of which were, in those days, "fixed" to the single arm mount.
The Nexstar 5i was considered to have a neutral balance on the arm while the Nexstar 8i was deemed back-end heavy. Thus according to Mike, a positive altitude setting would take advantage of the back-end heaviness of the N8i while the "neutral" N5i was better suited to remain negative. This also applied to the later, still "fixed" transitional "iSE"s.
Realising though the restrictions imposed by the fixed OTAs, many of us "i" series owners modified our 'scopes by installing "Ray's Brackets," which enabled the OTA to be removed from the arm so that other OTAs, (eg.refractors), might be attached and also allowed total mount base clearance, thus gaining zenith viewing.
Despite therefore changes in weight distribution, the positive altitude setting for the 8" prevailed as did the negative for the 5" and in truth, seems to work well with today's 5SE, 6SE and 8SE where the first two are considered neutral but the latter, still back-end heavy, despite the fact that these scopes can be balanced off the arm and then reattached at the appropriate spot.
So, in terms of the alignment procedures themselves, to take advantage of the original back-end heaviness of the N8i Mike advocated a positive altitude GoTo Approach culminating in a final right and down movement of the object in the EP to centralise it. With a negative altitude approach, he recommended the right and up final centralisation. This recommendation appears to have "stuck" because it works !
There is an additional feature to this. Back in September last year I wrote an article for CN on object centralisation following successful alignment of the 8" models for which I had the invaluable help of our CN colleagues Bob Griffiths and Tony Dralle who kindly carried out confirmative tests for me. What we found was that better tracking is achieved if the up / down movement is reversed depending on whether the object to be viewed is in the Eastern Hemisphere or Western. Take a look at the article if you wish. If you have any difficulty in finding it please let me know. It's called "A New Tracking Method for Nexstar Scopes" (or something like that -- I can't remeber exactly) !
I hope this answers your question. It is purely my interpretation of events and reasons. If others have any different theories and/or opinions, I would be grateful for their advice.
Best Regards,
Tel
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Truth is the cubed root of Verbosity.
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Bob Griffiths
Postmaster
Reged: 10/10/05
Posts: 6590
Loc: Frederick Maryland
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Radim:
Tel answered your question much better then I could have, but it really boils down to the fact that with the spur gears that are used in these scopes you just get better results by using the Right and Down buttons.. Believe me it really does not take long until you use those buttons and never give it a thought.. Your fingers just do the walking with no guidance at all from your brain...
You will find that if you are consistent in how you use the scope you can really get it to preform very well
Tels remarks about reversing the use of the buttons in the West actually is a natural progression of the same principle (reducing the play inherent with spur gears).. Believe me when Tel first came up with that "idea" I was pretty doubtful it would do much, if anything, to improve the accuracy.
In short I was wrong... So I now have the letters D and E stuck on the inside of my Observatory on both sides of the Shutter door.. .D = Down E = East To be honest the reversal has now become a habit and I no longer even have to think about it...
Bob G.
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CPC1100
Nexstar 8i + GPS & Rays Brackets
Denk S1 power switch
Orion 100 mm Refractor
Meade LXD 55 ...AR-5 127 mm Refractor
Exploradome Observatory S.I.E. (Smiling Irish Eyes)
Gerbring Heated Motorcycle clothing in the winter
39*21'03" N
77*28'12" W
The sky over my head....
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Radim
member
Reged: 11/06/05
Posts: 73
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Tel/Bob thanks for your answers and tips.
I wanted to ask you what is the fastest way of doing allignment? I thought and tried to do one-star allignment but it did not work precisely at all , I was out for almost 10degrees. So I moved to two-stars allignment which worked quite OK , not dead on but still within 32mm EP (8SE model).
Thanks
Radim
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OMC300 , SCT 8SE
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Tel
Post Laureate
Reged: 03/31/06
Posts: 3984
Loc: Wallingford England
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Hi Radim,
I don't know which 'scope you have but I think you are certainly on the right lines in using the "Two Star Align".
One Star Align is IMHO just a rudimentary means of getting the 'scope to track with an acceptance that GoTo accuracy will suffer.
Personally, I use the Auto Two Star Align with my Nexstar 8i. It saves me physically having to slew to the second star, and at the same time, it gives me some confidence that having programmed it for the second star, the OTA knows where I want it to go. In other words, the signs for a perfect alignment are looking good at this stage !
So, having set up my time site etc. and performed a "Calibrate GoTo", I slew the OTA manually as required, to the first star. I pick it up in my 9 X 50 finder, centralise it and then take a quick look in a 20mm EP I have in the OTA, confirming that it's there ! I do not press "Enter" at this stage even though the LCD is telling me to do so. Instead, I quickly replace the 20mm with the finder 'scope EP, (about a 26mm as far as I can guess), which provides me with crosshairs.
Thus, with my alignment star out of focus, (ie. looking like a "large-ish" doughnut), I then centralise its image on the crosshairs using, (because my 'scope is set to a |
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