Re: Mach2 model building and pointing with Sequence Generator Pro

Ray Gralak


Thanks for responding the for the suggestions. I have not used user profiles in the past, so that may be the SGP
issue. I will set one up. I do have the coordinates stored in the AP v2 ASCOM driver, using ASCOM platform 6.4
Okay, that's good. What kind of telescope are you using?

One thing I am wondering is, how does the mount ever get synchronized to the sky?
Using APPM is the most accurate way to synchronize the mount to the sky. As part of capturing sky data, APPM will synchronize the mount to the sky (a "RECAL").

Later, after a model is in use, the mount can be recalibrated using an ASCOM sync, but that assumes the calling program has accurately converted a plate solve's J2000 coordinates into the current epoch, and is accounting for refraction. Alternatively, using APPM's run tab is likely more accurate. APPM's "Run" tab, there are buttons that allow you to plate solve and/or RECAL the mount. The use of plate solving in APPM assumes it has been set up in APPM.

Can you also let me know where are the APPC logs stored?
You can use the APCC Log Zipper to find logs and to create a zipped file of the appropriate logs. You can run the Log Zipper utility from APCC's Tools menu.

Providing a dropbox link to the zipped set of the logs might be helpful. Please remember to indicate the calendar date and time, so we will know where to start looking in the log files.

-Ray Gralak
Author of PEMPro
Author of APCC (Astro-Physics Command Center):
Author of Astro-Physics V2 ASCOM Driver:

-----Original Message-----
From: [] On Behalf Of Steve Armen
Sent: Monday, October 19, 2020 8:39 PM
Subject: [ap-gto] Mach2 model building and pointing with Sequence Generator Pro

This is meant for Ray Gralak. With the new mach2 being controlled by SGP version and APCC/APPM
latest version I have had two opportunities to test.

It may well be I am doing something incorrectly in the process. Let me preface this with my old mach1 could use
SGP plate solve and sync, then pointing with coordinates with very accurate pointing results. I have carefully
checked any parameters set for the OTA and camera. Since plate solves are passing, I'm assuming the required
parameters are correct.

With the new mach2, here is the process I've been following:
1) Starting up, doing what I consider a good polar alignment with Sharpcap (3.2), then connecting with SGP.
2) Do a solve and sync with ASTAP (also tried platesolve2 with no difference in results) which is successful.
3) Try to slew to a target, e.g. Vega. The slew ends up with the target somewhere off in a corner or not even in the
field of view (~32' x 22').
4) OK, not totally unusual so then use the "center target" which is plate solve based which always worked in the
past. This moves the target somewhere ~ 10 arc min to the left of center and happily reports centering success.

Let me further explain, I have attempted this two ways.
1) No APCC/APPM run, just the steps above.
2) Use the APCC/APPM flow as I read it, I did setup horizon limit before starting.
a) power up, connect to APCC, park the mount at park 3, which always works!
b) try the homing under the AE tab
c) Run APPM to generate a sky model. So far have tried the small and medium models. All points plate solve

After the model run, I make sure both items below are selected:
Enable Pointing Correction
Enable Tracking Correction

When I try with either method 1 or 2 with or without model, the slow to object still has a large offset.

One thing I am wondering is, how does the mount ever get synchronized to the sky? The plate solve and sync in
SGP does not appear to be working. Does the model making process automatically sync the mount to the sky?

Can you also let me know where are the APPC logs stored?


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