Jump to content


Photo

Budget alt-az mount

  • Please log in to reply
18 replies to this topic

#1 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 04 July 2009 - 09:00 AM

I have a Orion Spaceprobe 130ST. It is 24" long and weighs 6.9lbs according to Orion. I do not know if this includes the rings. I like the scope - nice bright parabolic mirror. I do not like the EQ2 that came with it. Not because of the usual vibration complaints - doesn't bother me. I just don't enjoy observing when I am constantly fighting to understand and control an equatorial mount.

What are my alt-az alternatives? Low cost very important. Very light weight also important. I would like a mount that can be pointed at zenith.

I really don't know what is out there. The AZ4 looks like it might fit my requirements. Also thinking about the Ioptron Cube. As I mentioned the vibration I have learned to live with in a cheap mount and I figure if the GoTo works half the time is more than I have now. Other options?

#2 Lenardo

Lenardo

    Mariner 2

  • -----
  • Posts: 258
  • Joined: 19 Feb 2009
  • Loc: Ma

Posted 04 July 2009 - 11:57 AM

the cube works very well. the controls are easy to learn etc.

i own the cube gps and it works very well.

if aligned correctly-arrow pointing south, a good 2 star alignment and the mount being level, the goto works pretty much all the time.

#3 Preston Smith

Preston Smith

    The Travel Scope Guy

  • *****
  • Posts: 6051
  • Joined: 24 Apr 2005
  • Loc: Eureka, Pa

Posted 04 July 2009 - 12:06 PM

I own the basic cube and put it on a more solid tripod. It serves me well. The great thing about this mount is that if you move up to a more advanced mount you can keep the cube as a grab-n-go. FWIW: I only use the cube for my smaller 50mm-80mm refractors.

#4 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 04 July 2009 - 12:09 PM

What type scope are you using with the cube? My real concern with it is that the 130ST being a 5 1/2" plus the rings would stick out so far from the mount that it might cause too big a bending moment on it throwing it a little off balance.

#5 Lenardo

Lenardo

    Mariner 2

  • -----
  • Posts: 258
  • Joined: 19 Feb 2009
  • Loc: Ma

Posted 04 July 2009 - 05:34 PM

i'm using a 114mm reflector (4.5")-weighs about ~6 w/my hyperions) doesn't cause an issue. uses a normal vixen (i think) dovetail mount, just adjust for balance- loosen left nut rotate scope til horizontal, let go, if drops to rear, slide dovetail down, if drops to front, slide dovetail up, until it remains steady when released, tighten nut, once you have rotated the scope to vertical you are all set, i did it this way, and i have not had any problems with stability or goto once alignment is done.

your results might vary, but i like hte cube and will most likely upgrade to a minitower if and when i move up to a heavier tube -i also have an 8" dobsonian scope that is my main viewing telescope now.


oh ya, don't forget to change the time and your location in the cube, it's set for china by default if i remember correctly.

#6 TONGKW

TONGKW

    Apollo

  • -----
  • Posts: 1080
  • Joined: 16 Jan 2007

Posted 04 July 2009 - 10:14 PM

I have a Newtonian 130 mm f/5 OTA mounted on a Vixen Porta AltAz mount and the set up works very well.

K W TONG
----------------
C8 + CG-5GT, TSA102 + HEQ5 PRO, MK67 + Voyager Mount, WO ZS 80FD + Kenko NES, NexStar 6SE, WO Megrez 72 + Mizar K Mount, Mini Borg 50, C5, PST

Attached Files



#7 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 05 July 2009 - 06:27 AM

Thanks for the photo. Can you point your scope at zenith without hitting the tripod? Looks like it is close. I am considering this mount and the Astro-Tech Voyager Alt Az as well as the two I mentioned. The porta and voyager are a little more expensive but not a lot.

#8 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 05 July 2009 - 06:38 AM

i'm using a 114mm reflector (4.5")-weighs about ~6 w/my hyperions)


So the scope by itself weighs ~3? :lol:

Yours is close to my setup. Let me ask a use example query: Starting with the scope set up in park position with the tube rotated so the focuser is pointed west and the finder is on the south. When you go to polaris I assume the finder would be on top (also assuming you can see polaris from your location). Now if you slew to some southern oriented target does the cube rotate to keep the finder on top or is the finder now in some awkward unusable position?

Appreciate the help - this is still my primary choice if it will work.

#9 TONGKW

TONGKW

    Apollo

  • -----
  • Posts: 1080
  • Joined: 16 Jan 2007

Posted 05 July 2009 - 06:56 AM

Yes. The OTA would hit the tripod at zenith. If this happens I have to move the tripod round a bit.
The Voyager AltAz mount with a longer side arm should not have this problem.

#10 Bob Griffiths

Bob Griffiths

    Getting Grouchy

  • *****
  • Posts: 10620
  • Joined: 10 Oct 2005
  • Loc: Frederick Maryland

Posted 05 July 2009 - 12:34 PM

Why can't you use the EQ-2 BUT set it at 90 degrees and use it as an Alt/Azm mount...

I use an old EQ1 or EQ2 mount (who knows waht it is or even who made it) that way with my 100 mm refractor...I do not need the counter weight or the shaft ...

Bob G

#11 izar187

izar187

    Surveyor 1

  • -----
  • Posts: 1668
  • Joined: 02 Sep 2006
  • Loc: 43N

Posted 05 July 2009 - 02:15 PM

Why can't you use the EQ-2 BUT set it at 90 degrees and use it as an Alt/Azm mount...

I use an old EQ1 or EQ2 mount (who knows waht it is or even who made it) that way with my 100 mm refractor...I do not need the counter weight or the shaft ...

Bob G



Yes, try this first!
No purchase necessary.

#12 boydd

boydd

    Mariner 2

  • -----
  • Posts: 240
  • Joined: 07 Dec 2007

Posted 05 July 2009 - 03:24 PM

Why can't you use the EQ-2 BUT set it at 90 degrees and use it as an Alt/Azm mount...

I use an old EQ1 or EQ2 mount (who knows waht it is or even who made it) that way with my 100 mm refractor...I do not need the counter weight or the shaft ...

Bob G



Yes, try this first!
No purchase necessary.



The altaz mode works very well if you are willing to use a telrad/laser and manual slewing. Don't forget to balance properly. I bought the flexible shaft extensions for ease of use.

"Because it Works"
Dave Boyd

#13 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 05 July 2009 - 07:05 PM

[quoteThe altaz mode works very well if you are willing to use a telrad/laser and manual slewing. Don't forget to balance properly. I bought the flexible shaft extensions for ease of use.[/quote]

I actually tried this early in the year looking at Orion. I didn't really like the feel of it. Having heard the success others are having I guess I need to have another go at it. I think I have just made up my mind I don't like the EQ2 and need to reprogram my mindset to get over it - or shell out $300! Thanks All for the ideas.

#14 boydd

boydd

    Mariner 2

  • -----
  • Posts: 240
  • Joined: 07 Dec 2007

Posted 05 July 2009 - 09:06 PM

[quote name="Parker Fly"][quoteThe altaz mode works very well if you are willing to use a telrad/laser and manual slewing. Don't forget to balance properly. I bought the flexible shaft extensions for ease of use.[/quote]

I actually tried this early in the year looking at Orion. I didn't really like the feel of it. Having heard the success others are having I guess I need to have another go at it. I think I have just made up my mind I don't like the EQ2 and need to reprogram my mindset to get over it - or shell out $300! Thanks All for the ideas. [/quote]

Find someone to help you set this up correctly and reprogramming your midset will go away. Enjoy!

"Because it Works"
Dave Boyd

#15 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 06 July 2009 - 03:54 PM

I spent some time today trying to remember what it was about using the EQ2 in alt/az mode that I didn't like. First I would like to lose the counter weight but that is minor. The other thing was that all the locking controls are in awkward locations most of the time and I can't find them easily.

It occurred to me that since I would not be using it in eq mode I should be able to mount the OTA in the rings backwards - thus putting the locking controls on the same side as the focuser. That should help, unless I am missing something?

#16 boydd

boydd

    Mariner 2

  • -----
  • Posts: 240
  • Joined: 07 Dec 2007

Posted 06 July 2009 - 08:04 PM

I spent some time today trying to remember what it was about using the EQ2 in alt/az mode that I didn't like. First I would like to lose the counter weight but that is minor. The other thing was that all the locking controls are in awkward locations most of the time and I can't find them easily.

It occurred to me that since I would not be using it in eq mode I should be able to mount the OTA in the rings backwards - thus putting the locking controls on the same side as the focuser. That should help, unless I am missing something?



Keep thinking, keep going. You are on the right track. No matter an EQ, EQ in altaz mode, or pure altaz you will not loose the counterweights in some fashion if you want to do it correctly. Ignore the folks who complain about the pure altaz mounts locking down. Balance (physics), balance (physics), balance (physics). The EQ in altaz mode does not need a lockdown mode. The gears take care of any movement.

Part of the fun of this hobby is the techno weenie!

"Because it Works"
Dave Boyd

#17 gnowellsct

gnowellsct

    Fly Me to the Moon

  • *****
  • Posts: 6752
  • Joined: 24 Jun 2009

Posted 08 July 2009 - 12:31 PM

The obvious thing for a quality alt-az mount is a Super Polaris used in alt-az configuration. The SP goes for about $175 to $225 used.

That's about as low as I would care to go in terms of price.

super polaris in alt-az mode

good luck,
Greg N

#18 Parker Fly

Parker Fly

    Lift Off

  • -----
  • Posts: 23
  • Joined: 19 Feb 2009

Posted 08 July 2009 - 04:04 PM

The obvious thing for a quality alt-az mount is a Super Polaris used in alt-az configuration. The SP goes for about $175 to $225 used.

That's about as low as I would care to go in terms of price.

super polaris in alt-az mode

good luck,
Greg N


Any one know the approximate weight of this mount?

Also for anyone who might run across this thread through a search in the future - you can not use the EQ2 in Alt Az mode! It is physically impossible to turn the T handle all the way to 90. About 80 is all you can get before the handle hits the mount. You can not set it to zero as the counter weight hits the tripod.

I thought I had tried this early in the year but after tinkering today I realized what I actually did was loosen the Az lock at the base of the tripod and spin the whole unit on the tripod axis. It works but not well.

#19 davidpitre

davidpitre

    Soyuz

  • *****
  • Posts: 3574
  • Joined: 10 May 2005
  • Loc: Central Texas

Posted 08 July 2009 - 05:01 PM

I would look seriously at the Universal Astronomics mounts.
They are solid, come in many configurations, are inexpensive, and the owner will be glad to talk to you until you figure out which is right.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics