Hi Howard,

The document looks good to me.  I do have a question though...

I am presently running APCC v1.8.8.17.  I was reading your description of the "Dec Arc Tracking on a mini Dec-Arc-Model".  This is essentially what I have been doing for the last year and a half since I got my Mach2.  My APPM parameters are a little different - horizon limits and RA spacing - but I set up three lines with 2 or 3 degree declination spacing.  It works so well that I have lost track of where my guide scope and guide camera are stored.

I understand that the new version of APCC Pro has an "Enable Dec Arc Tracking" button somewhere [presumably in the pointing model tab].

My question is... If I upgrade to APCC Pro v1.9, what does the "Enable Dec Arc Tracking" button get me that I don't have now?  I read in the release announce by Marj that we get a "Declination-Arc tracking algorithm." and that "This new algorithm is an alternative to the normal all sky tracking model that APCC Pro uses."  However, I haven't figured out how the new algorithm improves on what I am doing now.

I'm one of those "if it isn't broke then don't fix it" adherents as far as my imaging software stack is concerned.  I have been waiting to upgrade to v1.9 and haven't really felt the need to do so since my current version is performing flawlessly.  I will upgrade if there is a performance advantage over what I am using now though.

Thanks in advance for your advice.

Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/