Re: APCC/APPM requirements for the Astro-Physics mounts.

I'd like to offer a new-customer perspective on this.  I came from a MyT and The Sky X and so had some concerns about a software based system as opposed to hardware/firmware, and what limitations this may impose.   I was not a fan of TXS generally, so was then not a fan of the … I'm not sure restrictions are so much the right word as perhaps hurdles you had to overcome when you wanted to use other software.  This despite it having been around forever and had a ton of interfaces/techniques documented.


I found the AP system a different world even if a lot of similarities.

It required APCC and APPM to build and use a model (and so far as I know that's the only way) just like TSX and tPoint.  And like TSX it has a ton of options and settings (though I will also say that the defaults are a lot more sensible and need less changing to just get started).  And like TXS (at the time) it is 32 bit only.  However…


It does not get in the way. 

It is possible to use the mount without APCC (through the ASCOM driver) though without the model, but with encoder benefit.  But I think rather pointless.


The use of APCC is transparent to other applications; it's just plain ASCOM.  While you can tweak things in APCC (e.g. limits), the application does not really 'see' that the mount is anything special.  I just converted to NINA and all was (almost) well.  The almost was frankly that I forgot to undo some special settings left over from TSX.


Now secondarily to that, NINA in particular has been customized so it can interact directly with APPM. You can actually use NINA to build your model; it does the work of invoking APPM, building and loading the model, you never need touch it.  I personally prefer to do it directly, but it's all in there.   An advantage of doing it from NINA is it can be pre-programmed to go off at a certain time, for hands-free model building.


I am to the point now that I only touch APCC once most nights -- at the end, I park from there instead of NINA, as I keep NINA and APCC's park defaults to different locations.


The only downside I've seen so far (again, as a new user) is the 32 bit limitations.  When using APPM itself (vs NINA or TSX) to control the camera, its memory limitations come into play.  However, these vanish if you tell APPM to use NINA or TSX (or probably others).  So it is really moot; people with large full frame cameras are better off just starting there, not trying to let APPM use the camera itself.  [Insert Ray's protest here, that the issue is really ZWO's and probably others lousy ASCOM driver memory utilizations, but from a user perspective it does not matter who is at fault -- just use the 64 bit application for camera and it is all moot].


My GUESS is also that doing these things in software vs firmware provide for a faster development cycle, and more flexibility since PC programs can grow faster on disk and computer memory than inside firmware.  In just the 3 months or so since I got my mount quite a few new features were added.


Short version: As someone coming from a "software" mount, the integration and interactions of APCC and APPM do not get in the way.  I think that's because Bisque was a software company that also builds hardware, but (my view) AP is a hardware company that also does software (well, Sirius Imaging does).


As to what's planned… I of course have no idea.



From: <> On Behalf Of Arvind via
Sent: Thursday, November 4, 2021 12:11 PM
Subject: [ap-gto] APCC/APPM requirements for the Astro-Physics mounts.


Hi, A-P team:


I am asking this for a future purchase, and hopefully for the benefit of others who might have a similar question.


So far I have been under the impression that to be able to build a pointing model and use it with any of the Astro Physics mounts, I had to use the APPM to build a model, and APCC to use that model with the mount to improve pointing & tracking accuracy; especially for unguided imaging to factor in real-world sources of errors even with near-perfect polar-alignment. Of course, one can choose NOT to do all this and just do autoguiding to provide the necessary feedback and still get wonderful results with A-P mounts.


Is my understanding correct on the need for APPM/APCC to fully benefit from encoders & unguided imaging with the A-P mounts? If so, is there a plan to move the model building & usage to the mount computer itself eventually to allow customers to use any software, or even a hand-controller, to coordinate model building & usage? Perhaps a firmware update to CP4/CP5. Is there any other performance-related functionality that is only provided as part of APCC/APPM software?


Thanks & best regards,




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