Re: [APML]:AP Goto Pointing accuracy

["Ian Turner" <skyshooter@mindspring.com>]

The Astro-Photography Mailing List
------------------------------------

Chuck

According to Roland who I just spoke with this morning about my results. He
say's that the biggest problems with gears are not cutting the gear teeth on
the Lath right after the Gear is turned. He say's  " U must not reposition
the Gear after U turn it to cut the teeth. He has apparently purchased a
gear cutting machine able to do this. He also mentioned that there are other
way's to achieve these results. One was by running the Gears in under
pressure.

He also mentioned that since this is a Goto system he couldn't have as tight
a backlash as per normal systems. I haven't taken it completley apart Chuck
but what I have seen have been small gears. I'm not sure how he does get the
PEC so good but I can E mail U a raw image from a 10 min unguided  CCD shot
of M16. Stars are perfect.

I saw this thing perform this trick at the winter Star party made me feel
alot better about selling some of my gear to fund this project.  

Ian
_________________________________________
                Ian Turner              
     Astrophoto and CCD Imaging Tips
http://www.mindspring.com/~skyshooter/                                      
                                                         
_________________________________________

----------
>From: Chuck Vaughn <aa6g@aa6g.org>
>To: astro-photo@nightsky.com
>Subject: Re: [APML]:AP Goto Pointing accuracy
>Date: Fri, Jul 24, 1998, 11:09
>

>You're saying the periodic error is 2" without any PEC? If so, what's the
>purpose of PEC? I'm a little hesitant to believe that as that is three
>times better than the Byers 11 5/16" gear. AP is not using a gear that
>large are they? I have a friend who has a Mathis 15" gear on his mount 
>and he claims 2-3". Most people don't have seeing good enough to be able
>to train the PEC for that small amount.