SGP Target DEC & RA out Platesolve to Mount/TheSkyX

Morning Guys need some help, having resolved an issue with Platesolve2 and APM directives by reinstalling the entire SGP software, platesolve is working, but this weir problem has rise with the DEC/RA coordination.

In 10Micron mount GM2000 I have a good PA (less 2" error), star alignment and Sky mapping with 30 extra points alignment RMS 4.2. After achieving at last Auto-focusing is good ‘V’ shape with a reflector Takahashi CCA250 telescope (not an easy feast believe me) I targeted IC 1396 DEC 57. 30 deg & RA 21h 30m 06s in the mount and TheskyX (please check log time 22.58.17).

In SGP under Sequence IC1396-1 the target was at DEC deg and RA 21h33m41s, you can notice that there was a large difference to the true coordination of IC1396.

If you look at the log time there is a line that mentions telescope -using offset sync option, showing the actual difference between true coordination and that SGP slew the telescope.

My telescope/mount I now is properly balanced and if I slew to IC1396 it hit the target and platesolve, so I believe I am left out something in SGP or tick the wrong box, if this is not the case I am totally lost of what is going on.

Please find the log.sg_logfile_20190810221143 - Copy.txt (893.1 KB)

Any help will appreciate.


I wonder if this is a J2000 vs JNow issue. SGP does everything in J2000 and it’s likely that your mount is reporting JNow coordinates. If so that would explain the difference.

Hi thanks answering, 10micron works with both J2000 and Jnow in any case the differences I am getting exceed that of J2000 to Jnow. I found the problem its relates to a setting in the mount Ascom , there is a setting in the HC whereby you allow sync (refine sync) when doing a mapping points model once completed you need to disable it both in the HC and Ascom. This allow SGP to communicate with the mount when platesolve, I still use the offset option in the platesolve menu.


Just for clarification here, SGP will translate between whatever the mount “speaks” and J2000 internally. This is assuming that the mount correctly tells us the coordinate epoch it is using.