A-P Guide scope bracket/Baader guide scope


Joseph Beyer
 

I was looking for user experience on the 10x60 Baader guide scope with Astro-Physics guider bracket and wondered if there is any potential need for special balancing when it is side mounted to the telescope. Given the location of the guide scope attached to the rear of the FSQ there is more weight on the left side which slightly pulls the scope left from Park 3 position even when perfectly balanced horizontally.  Has this small amount of weight imbalance been something others have compensated for in their rigs?  It doesn't seem like a large amount of imbalance but it's clear it's not in perfect balance at certain positions.

I purchased the guide scope for use with my Mach1/FSQ-106 rig about the same time I started using APPM.  Found the unguided mount would produce round stars at least up to 3 minutes which accommodated the exposures for my then Nikon D800 and my current ASI6200MM when imaging LRGB.  Since I could get good exposures with or without the guide scope I haven't been using it. Moving on to narrow band, the unguided setup looks pushed a bit with 5 minute subs and the stars are often a bit smudged.  Could also be in part attributed to seeing as exposures on some nights look better than others.  But since the guide scope is available I might as well use it. 

The FSQ setup weighs about 25 pounds in total balanced with 39 pounds of counterweights.  The guide scope with camera is about 2.4 pounds.  Not talking about a huge amount of weight relative to the main scope and counterweights.  It's likely the real answer is "depends on my results".  When I used it before along with APPM modeling, with 60-90 second exposures I saw no difference in star shape guided or unguided but I also didn't see anything that indicated it was destabilizing with rig either.  I'd ordinarily just go out and try it myself but the fall rains have arrived so not sure when my next opportunity will be.  Just wondered about other's experiences.

Joe    


R Botero
 

Joe

I doubt the mount will notice the difference; I would not worry. I have changed my Vario finder/guider a number of times as I add/change my tandem setup and the guiding is as good as ever (been using it since 2014). I’ve had it on an 1100GTO and now on a 1600GTO; both with and without APPM and it just works. No differential flexure versus the imaging scopes. As long as you have everything tightened up fine and no loose cables, you’ll be fine. 

Roberto


Joseph Beyer
 

Thanks for the confirmation Roberto.  I was assuming that would be the case but thought I'd check with someone who has more experience with it.  My setup is quite compact and I've done as much as I can to reduce the moment arm so the small amount of added weight is not likely to be a factor in guiding.

Joe