Re: Azimiuth Display around Park Altitude = 0


Ray Gralak
 

Hi Stacey,

I just updated to the newest version of APCC and the driver. I park at Park-2, which is basically azimuth=90,
altitude=0. When parked the altitude sometimes dithers a few arcseconds. With the new update I've noticed that
when the altitude dithers to a very small negative value (just a few arcsecs less than zero), the azimuth display
jumps from 90 to 270. I don't recall seeing this before the upgrade. Because of the weather, I haven't see whether
this has any effect on the dome slaving when the dome is sitting open at startup (cool down), the scope is at 90/0
and the dome is slaved to the scope. I hope doesn't try to do a 180 with each dither.
Alt/Az is being calculated from site latitude, RA, Dec and local sidereal time. When the mount is stopped RA is changing so depending on exactly when RA and sidereal time is polled there might be appear to be a slight change in Alt/Az. This was not changed recently.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro V3: https://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: https://www.siriusimaging.com/apdriver


-----Original Message-----
From: main@ap-gto.groups.io [mailto:main@ap-gto.groups.io] On Behalf Of Stacey Mills
Sent: Friday, March 6, 2020 6:59 PM
To: main@ap-gto.groups.io
Subject: [ap-gto] Azimiuth Display around Park Altitude = 0

I just updated to the newest version of APCC and the driver. I park at Park-2, which is basically azimuth=90,
altitude=0. When parked the altitude sometimes dithers a few arcseconds. With the new update I've noticed that
when the altitude dithers to a very small negative value (just a few arcsecs less than zero), the azimuth display
jumps from 90 to 270. I don't recall seeing this before the upgrade. Because of the weather, I haven't see whether
this has any effect on the dome slaving when the dome is sitting open at startup (cool down), the scope is at 90/0
and the dome is slaved to the scope. I hope doesn't try to do a 180 with each dither.

Join main@ap-gto.groups.io to automatically receive all group messages.