Return to the Cloudy Nights Telescope Reviews home pageAstronomics discounts for Cloudy Nights members
· Get a Cloudy Nights T-Shirt · Submit a Review / Article

Click here if you are having trouble logging into the forums

Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User

Equipment Discussions >> Mounts

Pages: 1
James Cunningham
Post Laureate
*****

Reged: 08/07/10

Loc: Maryland
Alignment with side by side scopes
      #5515543 - 11/12/12 06:50 AM

How do you get an alignment with scopes set up side by side? Can both scope be set to show the same thing? What other pitfalls are there to a dual scope setup? Thanks.
Jim


Post Extras: Print Post   Remind Me!   Notify Moderator  
Fred1
Carpal Tunnel
*****

Reged: 09/19/07

Loc: Somewhere in the Orion Spur
Re: Alignment with side by side scopes new [Re: James Cunningham]
      #5515875 - 11/12/12 11:59 AM

I use to do it the same way I would align my finder scope. I had the smaller scope in a set of adjustable tube rings. Align the mount to the main/larger scope and then align the smaller scope to the main scope with the tube ring screws. The only pitfalls I had was the hassle of the extra time in setting up, balancing, etc. and if the ring screws weren't tight enough the scope would have a tendency to slide inside the rings. Plus, on a GEM one scope would inevitably end up in a less than ideal position for observing. I'm visual only. I hope this helps

Post Extras: Print Post   Remind Me!   Notify Moderator  
hottr6
Carpal Tunnel
*****

Reged: 06/28/09

Loc: 7,500', Magdalena Mtns, NM
Re: Alignment with side by side scopes new [Re: James Cunningham]
      #5515920 - 11/12/12 12:30 PM Attachment (26 downloads)

Those side-by-side mounts are a bit of a marketing-man's wet-dream. They really don't work for visual; they are really designed for wide-field AP.

EXCEPT with Ken Dauzat's saddle, which allows the second 'scope to be accurately aligned with the first 'scope. I am able to get my 2 'scopes within seconds of each other, which makes A-B comparisons of planets at high mags a dream.

I set up both 'scopes in the saddle in my workshop, get them balanced, and then carry it out to the GEM. This is very awkward, and if I have long 'fracs mounted, the GEM head is above my head so it is quite a lift.

The other downside is that Ken is no longer in business, and his saddles are NLA.


Post Extras: Print Post   Remind Me!   Notify Moderator  
mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: Alignment with side by side scopes new [Re: hottr6]
      #5516090 - 11/12/12 02:16 PM

Side by side configurations can be aligned in a number of ways.

If one of the scopes is small enough then 3 point rings work very well. If you have larger scopes or need to swap scopes around then you need to look at the saddles themselves.

Up and down (tilt) can be adjusted using metal shims under the saddle mounting bolts. The shims should be very thin (think thick foil). Yes it's a bit time consuming but you end up with saddles that are well aligned. There is often enough play in the saddle mounting bolts to adjust for small amounts of side to side movement.

There are also a number of commercial adjustable saddles. ADM and APM both have saddles with addition tilt and side to side adjustments.

http://admaccessories.com/Miscellaneous_Max_Guider.htm


Using shims gets you saddles that are very close to alignment but it takes some work and if you use a variety of scopes with your side by side configuration you may find that the alignments of their dovetail bars may not be consistent.

The commercial adjustable saddles give you more flexibility and speed of adjustment but they add substantial weight and height and extra cost.

Once aligned the only real downsides to good solid side by side configurations are a) extra weight but this is often mitigated by moving the total mass closer to the mount compared to piggy back setups and b) balancing the scopes is more complex. It takes a bit longer to achieve balance in all directions.


Post Extras: Print Post   Remind Me!   Notify Moderator  
hottr6
Carpal Tunnel
*****

Reged: 06/28/09

Loc: 7,500', Magdalena Mtns, NM
Re: Alignment with side by side scopes new [Re: hottr6]
      #5516802 - 11/12/12 09:31 PM Attachment (9 downloads)

I made some mods by drilling some extra holes so I can move the saddles closer to each other. Yes, it is a struggle for a CG5-class mount.


Edited by hottr6 (11/12/12 09:47 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
hottr6
Carpal Tunnel
*****

Reged: 06/28/09

Loc: 7,500', Magdalena Mtns, NM
Re: Alignment with side by side scopes new [Re: mclewis1]
      #5516829 - 11/12/12 09:44 PM Attachment (16 downloads)

Wow, they're nice. Bit rich for me.

A major downside for the simpler designs is the use of the Vixen dovetail. Really, D-series saddles should be the minimum configuration, as in the more expensive models.

Adjusting with shims is an example in masochism. You would never want to disassemble it. With Ken's design, interchanging is easy, needing a leisurely 15 minutes to get everything swapped in and aligned.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1


Extra information
13 registered and 37 anonymous users are browsing this forum.

Moderator:  Dave M, richard7, bilgebay 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 703

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics