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dvb
Carpal Tunnel
Reged: 06/18/05
Posts: 1923
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I'm getting ready to pull the trigger on a new scope for use with the Mallincam. I had thought about putting my 10" f/5 Dob on my Atlas, but I'm thinking it will be pretty unwieldy, so I'm looking for something more compact. Here's my thinking so far:
C11:
-- a pretty good rep for quality optics
-- f/10 optics and a really long focal length -- so, needs lots of focal reduction.
-- Hyperstar capable, but I think I have too much Light Pollution to use Hyperstar (my location is pretty 'Orangy' according to the Clear Sky Chart).
-- I can seldom do more than a one-star alignment, because of limited viewing range (trees and buildings let me see slightly to either side of the North/South Meridian). I think the narrow field of the C11 would require better GoTos than I can manage.
SN10
-- A questionable record for quality control
-- kind of a project scope -- need to replace focuser (which I've already done on my SN8 -- I'll swap the JMI over).
-- Potential collimation hell
-- Nice fast native optics, at f/4
-- Nice wide-field of view, so more forgiving of gotos
-- Have to pay the the LX-75 mount, which I would sell.
-- I've been very pleased with the views through my SN8 (which I would also sell)
-- SN10 is way cheaper than the C11, but cost is not a crucial consideration. I want the right scope, regardless of cost.
-- SN10 has the potential for Wonky eyepiece positions, like all Newtonians, but I would start by making Wilcox Rings.
-- Neither scope will be used for Moon or planets.
So, I am leaning towards the SN10 for Mallincam, but am prepared to be persuaded that the C11 is the way to go.
Thanks for your thoughts!
 
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Skywatcher 10" f/4.7 Newt on Matilda
Skywatcher 10" f/4.7 Collapsible Dob
Meade 8" SN f/4
Celestron C8 SCT
Celestron C6 SCT
Skywatcher ED100
Skywatcher ED80
EQ6 Pro "Matilda"
AT Voyager
Skymaster 15x70
Mallincam HyperColor Plus
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HendyPhoto
Sith Lord
Reged: 08/09/06
Posts: 1496
Loc: Bountiful, Utah
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Hey DVB! Since you already have an SN-8, I would go for the C11. The C11 has a really long focal length for those small dso's. Hyperstar would be nice, but not necessary, and can always be upgraded later. F/4 is nice though! Good luck, that's a hard call!
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~jon
SparkCast
CGE1400XLT w/HyperStar
90FD 66SD C6-R SN-8
CPC1100XLT Hutech 20D
Manny-Mod Vixen Porta
Mallincam MCHP
SPC900NC
CG-5 GT
"Two things are infinite: the universe and human stupidity;
and I'm not sure about the universe." --Albert Einstein
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jgraham
Postmaster
Reged: 12/02/04
Posts: 5370
Loc: Dayton, Ohio
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Hmmm, your SN8 should be a nice scope as it is, but since you asked....
As you've already mentioned the C11 will need focal reducers to get the focal length down to something useable and you may end up fighting vignetting and field curvature on the way. In contrast the SN10 is designed to give a wide flat field and is in general a better imaging platform. If you call around you might be able to find a shop that will sell you the OTA by itself.
I've been using an LXD75 SN6 for a cople of years with no upgrades and no problems. I take that back, I did one upgrade; I added an electric focus drive to the stock focusser. That made my imaging life much easier. Adjusting the focus lock took a lot of the image shift out of it.
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-John
================================================
Homebuilt scopes from 4.25-16.5"
Meade LXD75-N6/SN6/SC8, DSX-90, ETX-60BB, ETX-125PE, DS-2130
Orion StarBlast, BinoViewers, Coronado PST
Rebel XT/XTi, DSI Pro (I & II), DSI, LPI, Electronic Eyepiece, Phillips SPC900NC
Tasco 60mm Refractors
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Astrojunk
member
Reged: 11/02/06
Posts: 82
Loc: Australia
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The most popular setup in Oz seems to be a 10" F5 on an EQ6. Works very well and the 1250mm focal length seems to suit the 1/2 inch chip very well too for most dso's.
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Astrojunk
20" f5 Alt Az Newtonian
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dvb
Carpal Tunnel
Reged: 06/18/05
Posts: 1923
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So, mounting my 10" f/5 Dob on the EQ6/Atlas is back in the runnning!
I had planned to give the 10" f/5 a try, but was unable to locate rings for it -- it's a 10" Antares/GSO, and my local shop could only get Skywatcher rings, which are about 1/2" too narrow. I ordered Antares rings, but they have not shown up, and I suspect they are no longer being produced, as Antares no longer produces a 10" Newt. I haven't seen 10" Antares rings on the net lately.
I've been reluctant to order Parallax rings, cuz of the expense (about $250.00), and not knowing if the resulting set-up would work -- I'd be leaving the altitude bearings on the Dob, so that I could still use it as a Dob. For Parallax rings, I'd need a decent mounting plate, and should likely convert the EQ6 to a Losmandy-style saddle with the ADM adapters (another $200.0). Still cheaper than either an SN10 or a C11, but probably more unwieldy than either.
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Skywatcher 10" f/4.7 Newt on Matilda
Skywatcher 10" f/4.7 Collapsible Dob
Meade 8" SN f/4
Celestron C8 SCT
Celestron C6 SCT
Skywatcher ED100
Skywatcher ED80
EQ6 Pro "Matilda"
AT Voyager
Skymaster 15x70
Mallincam HyperColor Plus
Edited by dvb (04/21/08 10:15 AM)
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Bowmoreman
Carpal Tunnel
Reged: 09/11/06
Posts: 2992
Loc: Bolton, MA
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Quote:
So, mounting my 10" f/5 Dob on the EQ6/Atlas is back in the runnning!
I had planned to give the 10" f/5 a try, but was unable to locate rings for it -- it's a 10" Antares/GSO, and my local shop could only get Skywatcher rings, which are about 1/2" too narrow. I ordered Antares rings, but they have not shown up, and I suspect they are no longer being produced, as Antares no longer produces a 10" Newt. I haven't seen 10" Antares rings on the net lately.
I've been reluctant to order Parallax rings, cuz of the expense (about $250.00), and not knowing if the resulting set-up would work -- I'd be leaving the altitude bearings on the Dob, so that I could still use it as a Dob. For Parallax rings, I'd need a decent mounting plate, and should likely convert the EQ6 to a Losmandy-style saddle with the ADM adapters (another $200.0). Still cheaper than either an SN10 or a C11, but probably more unwieldy than either.
I'm, like, having a deja-vu all over again flashback with this thread, man! 
Seriously, you are going through EXACTLY what I was going through as part of my recent acquisition of a (used) CGE...
Originally I was thinking of using my XT10i OTA (1200 f4.7)... but I just kept coming back to:
"huge", "unwieldy", mega rings needed... did I mention HUGE?
So then I was thinking 8" or 10" SN8???
I finally settled on the 8" SN8 (Purchased used) because it is quite a bit lighter - which easily allows me to do a side by side with my TMB80SS and quality ADM SBS tandem arrangement. I'm going to start with the stock SN8 rings (and I'll fashion Wilcox rings), but may hafta end up with the Parallax rotating rings if I need to and think the SN8 is a long-term keeper.
I think if the SN10 is the only OTA on your EQ6, it'll work ok for you, but I would worry if you were going to move to side by side, and/or tandem arrangement with any other OTA - you'd be getting pretty heavy for an EQ6.
Don't remember from your OP, but do you still have the SN8? If so, why not try that first? If you don't have it, and aren't going for tandem/piggyback, then go for the SN10.
I would favor the SN10 over the C11 due to much faster, flatter field and no vignetting.
Now, if you are doing all this NOT in a permanently mounted observatory; this might change things a bit (I know it would for me).
Ultimately, unless I find that I'm super thrilled by the SN8, it will ultimately be only a way station towards either a C11 or C14 hyperstar... though, I do have some concerns about LP at my site (solidly Orangish)... I wish there was some definitive way of "knowing" a-priori, whether, or not, Hyperstar will work for a given site...
The ADM stuff isn't super cheap, but it IS nicely made (at least the first piece that I have - the SBS CGE sidebyside adapter for CGE - the rest - tandem saddles, dovetail plates and 125mm rings arrives tomorrow!)...
In my case it was about $500 total for ADM stuffs needed for complete side by side setup; I'm guessing that all the ADM stuff in total weighs around 10 pounds or so...
The SN8 weights 23.5 pounds, I figure a pound for Mallincam, another 2 pounds for my STV eFinder and mounting head/hardware for it, 6.5 pounds for the TMB 80 SS, and then another couple of pounds for EPs, etc...
All total around 44-45 pounds... I was worried I couldn't handle the SN10 (doesn't it weigh something like 36 pounds?) as I would be getting guite close to the upper end of the CGE.
Again, my case constraints were:
1) permanent, pier-mounted (most of the time) in an observatory
2) had to serve combo uses for classic AP and Mallnincam
3) really want dual scopes
4) I'm limited to an Observatory section of my obs that is only 6.5' wide... that 10" f4.7 OTA is just too long...
I did a LOT of research on how to mount that f4.7 OTA, but in the end decided to not go that route, when a great deal on a local (pickup!) SN8 came my way.
Again, I'd maybe be leery of the weight of an SN10 on an EQ6...
clear enough skies
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Dave
Ustream
YLive
XT10i, RTP, CGE, R200CF, TMB80SS
31T5, 22T4, 13Ethos, 8Ethos, TV 3-6 Zoom; Paracorr
MallincamColorHyperPlus,SBIG STV&237A;CanonRebel Xti
WilderSkiesObservatory(BYO #90)
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smokin oakum
Pooh-Bah
Reged: 09/24/07
Posts: 1426
Loc: Wilmington, NC
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Well, I just got off the phone after buying the 14CGE, and a set of rings for my 12" Orion, so I guess I would have to say either one is a fine choice!
Neil
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Broadcasting live views of the night sky @
Sparkcast
C11 CGE / Hyperstar
MallinCam Hyper Plus Color
Orion 12" XTi f/4.9
MoonLite Focuser
Round Table Platform
12" Parralax rings
Cape Fear Astronomy Club
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richs
member
Reged: 01/21/08
Posts: 51
Loc: California, USA
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Just thought I'd through my 2 cents worth in here. Unless I'm seriously missing something here, when a fast scope is used unless it is a relatively large scope, the image is going to be much smaller, IE much less magnification. I don't like to go over board on magnification but I like a nice sized image if at all possible. I have found in the past that most objects are better when they are larger, especially fuzzes as they are not crisp to begin with. I just purchased a used c-11 to go on my relatively new CGE to gain primarily more aperture but also it will handle and give more magnification. I set it up last night for the first time but just visual to get used to it. I was blown away when I stuck a Pentax 7mm in it for Saturn at 400x, the image was very crisp, I would never have gone that high with my c-8  Just some thoughts.
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RichS15" Obsession10" Meade LX200 GPS8" Celestron NexStar GPSCelestron Carbon Fiber C-11TEC 140 APODayStar .5a Ha Solar FilterCelestron CGEOrion AtlasMallinCam Hyper Color PlusSpeco 9" CRT monitorMarshall 4" LCD MonitorCelestron Sky ScoutDew Buster
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dvb
Carpal Tunnel
Reged: 06/18/05
Posts: 1923
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Thanks, all, for your thoughtful responses.
Dave, I have used the SN8 with the Mallincam, on my one and only deepsky opportunity -- It was great! The Leo galaxies aren't even visible with the SN8 from my urban sight, but showed up nicely with the Mallincam in the SN8. M66 looked lop-sided, just like the photo in O'Meara's book.
I could just keep the SN8, but have a store credit and some aperture fever, hence the upgrade.
If I was doing DSLR photography, I'd probably stay with the SN8, so that I could accommodate a guide scope etc. I'm thinking that for the Mallincam, I won't need a guidescope -- I don't think it would show my targets anyway. The SN10 OTA is rated at 30 lb., so I think it should be find on the EQ6/Atlas.
Playing off image size/ focal length v. f/ speed seems to be the basic struggle in this business. My views of Saturn in the SN8 and Mallincam were less than impressive. The Moon was OK, but no substitute for direct viewing. I guess that is part of the argument for the SN10 -- a bit more image scale (1000mm v 800mm) without sacrificing speed.
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Skywatcher 10" f/4.7 Newt on Matilda
Skywatcher 10" f/4.7 Collapsible Dob
Meade 8" SN f/4
Celestron C8 SCT
Celestron C6 SCT
Skywatcher ED100
Skywatcher ED80
EQ6 Pro "Matilda"
AT Voyager
Skymaster 15x70
Mallincam HyperColor Plus
Edited by dvb (04/21/08 11:54 PM)
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David Pavlich
Postmaster
Reged: 05/18/05
Posts: 6542
Loc: Mandeville, LA USA 30.38 X 90....
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I was going to suggest the C11 earlier, but since I had one on A-mart for sale, I didn't say anything. Now that I have a sale pending on it, I can place my vote for the C11. Just terrific optics and there's always that Hyperstar option.
David
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A few scopes and mounts.
Proud Member; PAS NOLA,
Life expectancies would go WAY up if green vegetables smelled like bacon...
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dvb
Carpal Tunnel
Reged: 06/18/05
Posts: 1923
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Hi David,
I saw your C11 on A-Mart and lusted after it mightily! Glad you got a sale on it.
By the way, no observatory in my immediate future, so its pack it out, set it up, strip it down, pack it each time.
Which is exactly what I'm doing tonight -- hope the Fullish Moon doesn't wipe me out. I'm giving the 152mm f/6.5 a try, I hope.
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Skywatcher 10" f/4.7 Newt on Matilda
Skywatcher 10" f/4.7 Collapsible Dob
Meade 8" SN f/4
Celestron C8 SCT
Celestron C6 SCT
Skywatcher ED100
Skywatcher ED80
EQ6 Pro "Matilda"
AT Voyager
Skymaster 15x70
Mallincam HyperColor Plus
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Astrojunk
member
Reged: 11/02/06
Posts: 82
Loc: Australia
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Continuing on an area mentioned by Richs and dvb, image scale IS focal length, much the same way magnification is measured by dividing the telescope fl by the eyepiece fl.
This means that the very first consideration in looking for a scope is at what fl do you wish to image?
Then you decide on (amongst a million other factors) the most aperture that you can get at that fl. The newtonian route is handy as it keeps the cost/fl down but sacrifices size/ease of mounting.
The only answer is to buy one of everything 
Those that have joined me on my channel know that I spend just as much time with my 80mm guide scope as I do with my 20" dob due to the abundance of diffuse nebulae, globular clusters and open clusters that are no use at long focal lengths
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Astrojunk
20" f5 Alt Az Newtonian
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Bowmoreman
Carpal Tunnel
Reged: 09/11/06
Posts: 2992
Loc: Bolton, MA
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Neil: congrats on getting the CGE14! Did you get Hyperstar (or Hyperstar ready for it?)
dvb: glad to hear the SN8 worked out well (since I'm going that way!) 
dvb, David, Astrojunk: I'm finding this a really interesting discussion. As you guys know, I'm selling my f/l 900mm 100ED APO, and am "replacing" it with the SN8 (800mm f4, 200mm Aperture) - about the same focal length (and hence image scale), but way, way faster... (just got the MoonLite installed on it last night, and then collimated - THAT was an adventure!!!)
Anyways, I have been playing around with the CCDCalc program (the one that comes with Ron Wodaski's The New CCD Astronomy), and I wonder about the real ability to get a completely and totally different image scale with a C11.
Here's why: The C11 is 2800mm focal length at f10...
If you use the MFR3 on it, I believe you get a focal reduction of .33 right? Well that makes it a 924mm focal length scope at f3.3, which isn't that much different from the SN8's or 10's of this world (800mm and 1000mm respectively, both at f4), so won't the image scale be very similar?
And, if you do NOT use the focal reducers, the focal length is much longer (hence different scale and more magnification), but its quite slow (I.e. the same "issue" I was having with my f9 refractor...), limiting your targets to only the very brightest...
Could you not, just as easily, get a more dramatic change in scale (i.e. increase magnification), by putting a 2x barlow on the SN8 or SN10 (in the case of SN8 turning into an f8, 1600mm)???
I'm trying to see (with the calculations), why it would not always be beneficial to go for the combo of as much aperture and starting as fast as possible (simultaneously). Seems to me that this gives the most flexibiltity (via FR's and/or barlows), since if you start with a faster scope (SN's at f4, or C11's with Hyperstar) you can feasibly barlow them without making em too slow, and since they have quite large aperture for their speed.
The "native" C11, starting at f10, seems, based on the math, to be sub-optimal (in the same way my ED100Sf at f9 was suboptimal.
Obviously, for planetary purposes (because they are so bright), barlowing, or super long focal lengths are less an issue because speed isn't needed as much...
But for fainter, DSO's, slow and long would be an issue I would think...
Or am I completely missing something here?
clear enough skies
--------------------
Dave
Ustream
YLive
XT10i, RTP, CGE, R200CF, TMB80SS
31T5, 22T4, 13Ethos, 8Ethos, TV 3-6 Zoom; Paracorr
MallincamColorHyperPlus,SBIG STV&237A;CanonRebel Xti
WilderSkiesObservatory(BYO #90)
Edited by Bowmoreman (04/22/08 07:02 AM)
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smokin oakum
Pooh-Bah
Reged: 09/24/07
Posts: 1426
Loc: Wilmington, NC
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Hey David! Thanks for the comments. I ended up getting the 14"CGE, but for right now the tube is being backordered on purpose. I'm just getting the CGE mount right now, and putting my 12" Orion on it with rings. In about 3 months I'll get the SCT OTA, and fit it with the hyperstar.
On the subject of the CCD calc program, I think image scale wise, you are right on the money, but don't forget that the bigger the aperture the more light gathering ability the scope will have, thus the C11 will out perform the SN8 on gathering light, but you are right, the image scale will be the same.
To me, the big plus with the C11, is the ability to have so many fl to work with. My 14CGE will be able to run from F/11 all the way down to F/1.9! That gives me the ability to do all kinds of changes to it for everything under the sun, or should I say moon. In heavy LP, you might actually not want you scope running too fast, and having the choice of how fast your scope is depending on what the conditions are, makes it very versatile.
Just my 2 cents.
Neil
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Broadcasting live views of the night sky @
Sparkcast
C11 CGE / Hyperstar
MallinCam Hyper Plus Color
Orion 12" XTi f/4.9
MoonLite Focuser
Round Table Platform
12" Parralax rings
Cape Fear Astronomy Club
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divers
sage
Reged: 01/21/08
Posts: 244
Loc: Apopka, FL
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Watching Lars last night with his 10" f/6 looking at the Hickson 50 gave me lots of practical knowledge. You guys with the big scopes no matter 11 or 14 are going to get a treat. Hope you broadcast! I am still happy with my little 7" Mak. Maybe someday if I get an observatory I will get a "big in". I think this video thing is going to be writing new rules for scopes.
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Intes M703D 7" Mak
Siebert 7mmUltra and 13mmUltra and 36mm Observatory
Siebert 2x 2" Barlow
WO Carbon Fiber (2") Dielectric Diagonal
Giro 2 on a Losmandy tripod with 12" extension.
Sky Commander DSC
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Astrojunk
member
Reged: 11/02/06
Posts: 82
Loc: Australia
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Top choice on the C14 with hyperstar. I plan to get one of these and a Paramount ME one day to do my asteroidal research. Dream on ...
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Astrojunk
20" f5 Alt Az Newtonian
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midway199
super member
Reged: 04/21/04
Posts: 108
Loc: Illinois
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Quote:
If I was doing DSLR photography, I'd probably stay with the SN8, so that I could accommodate a guide scope etc. I'm thinking that for the Mallincam, I won't need a guidescope -- I don't think it would show my targets anyway.
I wouldn't dismiss the posibility of autoguiding. Why not give your images the very best chance of showing as much detail as possible? With tools like PEC and autoguiding, you would be getting the most accurate tracking possible from your mount. We all want that, whether we are taking 30 second subs for formal CCD astrophotography post-processing or displaying 30 - 60 second astro-video images on our monitors.
Something to think about...
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Matthew Sherman
StellaCam 3
Celestron NexStar 11 @ f/3.3
Starmaster 12.5"
Starmaster 18"
Tom Osypowski Equatorial Platform
Butterfield East Video Observatory
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