Plate solve troubles

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Re: Plate solve troubles

#11

Post by admin »

Hi,

glad to hear that you have it working :)

The offset may be down to a difference in co-ordinate system. The plate solving engine works in J2000. Your mount may work in J2000 or JNOW and should report which to SharpCap. SharpCap will take account of the difference if the mount reports correctly.

Look in the log for these entries when plate solving

Code: Select all

Info   	15:47:02.762472	#1 	Mount reports JNOW, converting results position from RA=05:35:20,Dec=-05:18:31 (J2000)									in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()
Info   	15:47:02.871000	#1 	Conversion result is RA=05:36:22,Dec=-05:17:54 (JNOW)																	in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()
Info   	15:47:02.871634	#1 	Field solved to RA=05:36:22,Dec=-05:17:54, field Size {Width=1.552744, Height=1.140304}									in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()
Debug  	15:47:02.872269	#1 	Notification (Status=OK): Plate solve succeeded, position found to be RA=05:36:22,Dec=-05:17:54 (JNOW, offset of 4.11 degrees)				in void SharpCap.UI.NotificationViewModel.DisplayMessage(NotificationMessage message)
Info   	15:47:03.885444	#1 	Before Sync mount is at RA=05:37:17,Dec=-01:11:23																		in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()
Info   	15:47:04.907126	#1 	After Sync mount is at RA=05:36:22,Dec=-05:17:54																		in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()
Debug  	15:47:04.907126	#1 	Notification (Status=OK): Mount synced to RA=05:36:22,Dec=-05:17:54, re-centering on target at RA=05:37:17,Dec=-01:11:23 (offset of 4.11 degrees)				in void SharpCap.UI.NotificationViewModel.DisplayMessage(NotificationMessage message)
Info   	15:47:05.918019	#1 	Before Slew mount is at RA=05:36:22,Dec=-05:17:54																		in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()
Info   	15:47:06.931451	#1 	After Slew mount is at RA=05:37:16,Dec=-03:17:54																		in async Task<bool> SharpCap.ViewModels.PlateSolveAndResync.SolveAndSync()

You can see that in this case the mount is JNOW and SharpCap is dealing with the discrepancy. Also you can see the co-ordinates of the mount before and after each stage of the procedure. If you choose a known bright star as your initial target you can check the co-ordinates of it against those shown in the log to work out what is going on.

cheers,

Robin
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Re: Plate solve troubles

#12

Post by astrorunner »

Robin,

Thanks again for information. I finally had a night to test things out again. For some reason, tonight even though SharpCap said it was successful with plate solve, the coordinates were far off. Not sure what happened. I looked at the log file like you mentioned, and I could not see any entry for "JNOW" anywhere around the time frame of the plate solving. I do see J2000.

Code: Select all

Debug  	21:41:03.150949	#1 	Notification (Status=OK): Plate solve succeeded, position found to be RA=00:30:56,Dec=+89:27:40 (J2000, offset of 0.24 degrees)				in void SharpCap.UI.NotificationViewModel.DisplayMessage(NotificationMessage message)
I will need to do more testing. I got a late start tonight and will have to pack up but more clear skies soon.
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Re: Plate solve troubles

#13

Post by admin »

Hi,

if there is no mention of JNOW in the log it could be because either your mount works in J2000, or your mount works in JNOW but reports J2000 (which would cause an offset issue)

Which ASCOM mount driver are you using?

cheers,

Robin
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Re: Plate solve troubles

#14

Post by astrorunner »

There is an ASCOM window that pops up with either SkyX or with your software, but unless I have the mount hooked up I can't pull details from that window. Looking on the harddrive, there's an "ASCOM Diagnostics" program that says "ASCOM Platform 6.3-6.3.0.2821".

I will see if there are updates to ASCOM, I don't remember it updating in a while.

-- late edit: I just upgraded ASCOM to the latest version, 6.5 SP1-6.5.1.3234. If the wind dies down I will try the plate solving again soon.
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Re: Plate solve troubles

#15

Post by admin »

Hi,

updating the Ascom platform is definitely a good idea, but what I was really trying to find out is what mount you are using an what software you installed to allow your computer to talk to it. For instance if you have a Skywatcher mount then you might install either EQMOD or SynScan software. If you have a Celestron mount you might install CPWI. If you look in the hardware settings page in SharpCap, the name that you've selected in the mount choice drop-down is what I need to know.

Cheers, Robin
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Re: Plate solve troubles

#16

Post by astrorunner »

Hello again!

The name of the mount for "Select Hardware" in SharpCap is "EQMOD ASCOM HEQ5/6".

The mount is an Orion Atlas Pro. The software I use to point the scope is TheSkyX.

Bert
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Re: Plate solve troubles

#17

Post by admin »

Hi,

does it help at all if you configure EQMOD to use the JNOW epoch as shown here : https://www.cloudynights.com/topic/7083 ... -question/ (fourth post down).

You should also try to setup TheSkyX to use JNOW co-ordinates when sending positions to the mount - not sure how that is configured in TheSkyX (I haven't used it).

Making those changes should make the co-ordinate systems consistent (the plate solver still runs in J2000, but SharpCap will recognise the need to convert that to JNOW due to the EQMOD change).

Robin
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