No astronomy tonight however
Sync & ReCenter
Forum rules
If you have a problem or question, please check the FAQ to see if it already has an answer : https://www.sharpcap.co.uk/sharpcap-faqs
If you have a problem or question, please check the FAQ to see if it already has an answer : https://www.sharpcap.co.uk/sharpcap-faqs
-
kaymann
- Posts: 131
- Joined: Thu Jun 16, 2022 2:59 pm
- Location: https://azkayfes.blogspot.com/
Re: Sync & ReCenter
Also, I can remove any mount injected backlash adjustment if necessary (50 or 60 keeps my buttons lively which is also what the Celestron manual recommends)?
No astronomy tonight however
No astronomy tonight however
-
admin
- Site Admin
- Posts: 13523
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: Sync & ReCenter
Hi,
I'm afraid it's not obvious from the ASCOM log which one was carried out from CdCiel - probably at about 8:30-8:40pm from the slightly different commands seen there, but the slews in that section of the file seem the same in terms of the logged info as the SharpCap ones. Interestingly there are entries in the ASCOM log about 'slewoffset', but they seem to imply that it has no value and is being ignored.
cheers,
Robin
I'm afraid it's not obvious from the ASCOM log which one was carried out from CdCiel - probably at about 8:30-8:40pm from the slightly different commands seen there, but the slews in that section of the file seem the same in terms of the logged info as the SharpCap ones. Interestingly there are entries in the ASCOM log about 'slewoffset', but they seem to imply that it has no value and is being ignored.
cheers,
Robin
-
kaymann
- Posts: 131
- Joined: Thu Jun 16, 2022 2:59 pm
- Location: https://azkayfes.blogspot.com/
Re: Sync & ReCenter
"Hmm - any way that you can kick off a GOTO movement from another application and see if the mount ends up at exactly the target co-ordinates or a little bit off?"
Looks like the wind will die down enough for dust turbulence free viewing tonight I will give it a try...
Looks like the wind will die down enough for dust turbulence free viewing tonight I will give it a try...
-
kaymann
- Posts: 131
- Joined: Thu Jun 16, 2022 2:59 pm
- Location: https://azkayfes.blogspot.com/
Re: Sync & ReCenter
Well last night was a bust - my tracking error was huge and a mess. CDC was about half in error as SC. So I told CDC to slew to Arcturus noticed the error then manually centered Arcturus and told CDC to sync the mount. I then told CDC to again slew to Arturus and got the same error again. Syncing with CDC and simply telling SC to goto (no plate solving) produced a CDC sized error.kaymann wrote: ↑Tue May 07, 2024 3:42 pm "Hmm - any way that you can kick off a GOTO movement from another application and see if the mount ends up at exactly the target co-ordinates or a little bit off?"
Looks like the wind will die down enough for dust turbulence free viewing tonight I will give it a try...
I have not much more I can go on other than making sure the mount does not have some setting somewhere that is cause the last minute move and resulting error...
Ascom file split to fit file size
-
kaymann
- Posts: 131
- Joined: Thu Jun 16, 2022 2:59 pm
- Location: https://azkayfes.blogspot.com/
Re: Sync & ReCenter
So I looked at every setting available to the hand controller:
I found a cone value of 2' 55" I reset that to zero as I have no idea where that figure came from. Obviously I can add it back in.
I found the DEC Index set at 89° 25' 01" I reset that to 90°, I can add that back in if needed.
My simple thought is these values will be calculated and fed into the mount on the next hand controller sync when I do calibration stars from the hand controller next time out.
I also see I can calibrate the RA switch in case it is causing my errors...
Finally, I can initiate a GoTo Calibration which will change my final comeback slew speed (might be to slow)
Either of the two above could problems solvers for me
Everything else looked status quo as far as I can tell... But what do I know. This is obviously not a SC issue so I thank you for your time and consideration Dr Glover. I will work through this as best I can and report my end results as it could possibly help someone in the future.
I found a cone value of 2' 55" I reset that to zero as I have no idea where that figure came from. Obviously I can add it back in.
I found the DEC Index set at 89° 25' 01" I reset that to 90°, I can add that back in if needed.
My simple thought is these values will be calculated and fed into the mount on the next hand controller sync when I do calibration stars from the hand controller next time out.
I also see I can calibrate the RA switch in case it is causing my errors...
Finally, I can initiate a GoTo Calibration which will change my final comeback slew speed (might be to slow)
Either of the two above could problems solvers for me
Everything else looked status quo as far as I can tell... But what do I know. This is obviously not a SC issue so I thank you for your time and consideration Dr Glover. I will work through this as best I can and report my end results as it could possibly help someone in the future.
-
admin
- Site Admin
- Posts: 13523
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: Sync & ReCenter
Hi,
thanks for reporting back on your latest testing - it's particularly interesting that the error from CdC is half that from SharpCap 'solve and sync' and matches a SharpCap plain GOTO. That ties in nicely with the my analysis in post #9 above - that the GOTO is ending up in the wrong position and the way that SharpCap handles the solve and sync ends up doubling the error. I'm going to try to fix that in SharpCap (in the sense of removing the doubling of the error), since that's definitely a SharpCap issue.
Otherwise, as you say, somewhere in the internals of the mount or the ASCOM driver it isn't quite following instructions. Since you tried two different ASCOM drivers I am going to suspect the mount/handset itself, but its hard to be sure. I would hazard a guess that the cone value and other offsets may have been set up if you did a 3-star align at some point in the past (one star just gets you home position offset, two stars can work out polar align error as well, three can work out cone error too.)
Good luck!
Robin
thanks for reporting back on your latest testing - it's particularly interesting that the error from CdC is half that from SharpCap 'solve and sync' and matches a SharpCap plain GOTO. That ties in nicely with the my analysis in post #9 above - that the GOTO is ending up in the wrong position and the way that SharpCap handles the solve and sync ends up doubling the error. I'm going to try to fix that in SharpCap (in the sense of removing the doubling of the error), since that's definitely a SharpCap issue.
Otherwise, as you say, somewhere in the internals of the mount or the ASCOM driver it isn't quite following instructions. Since you tried two different ASCOM drivers I am going to suspect the mount/handset itself, but its hard to be sure. I would hazard a guess that the cone value and other offsets may have been set up if you did a 3-star align at some point in the past (one star just gets you home position offset, two stars can work out polar align error as well, three can work out cone error too.)
Good luck!
Robin
-
kaymann
- Posts: 131
- Joined: Thu Jun 16, 2022 2:59 pm
- Location: https://azkayfes.blogspot.com/
Re: Sync & ReCenter
The weather finally cooperated and got back into my discoveries. The setup included working over the backlash in my mount (I am not a professional and it takes me a while to only get it okay), resetting the scope to default, conducting a PoleMaster Polar Alignment. I then did a mount calibration (takes only seconds). I then conducted a two-star alignment, followed by two stars calibration (this is where the cone info comes from):
1) Connected Cartes du Ciel and when it slews to objects and syncs it is nearly spot on (close enough for me).
2) However, SC still more than doubles that error when it PS's and syncs.
3) It is interesting when I SharpCap PS and Sync and then go to CdC and connect the scope, CdC knows that the object has been moved to the wrong spot and correctly shows the star in the wrong spot that SC moved it to...
So, the question for me is why the mount movement after getting it almost right, I was really hoping the mount calibration was going to take care of it, but no, so my investigation continues... This is something I have to work out - this is informational only.
1) Connected Cartes du Ciel and when it slews to objects and syncs it is nearly spot on (close enough for me).
2) However, SC still more than doubles that error when it PS's and syncs.
3) It is interesting when I SharpCap PS and Sync and then go to CdC and connect the scope, CdC knows that the object has been moved to the wrong spot and correctly shows the star in the wrong spot that SC moved it to...
So, the question for me is why the mount movement after getting it almost right, I was really hoping the mount calibration was going to take care of it, but no, so my investigation continues... This is something I have to work out - this is informational only.