Hi, everybody.
I browsed the forums a bit for other meridian flip questions, particularly those on Celestron mounts but didn’t find anything that seemed to entirely correspond to my experience last night.
In short: my scope tried to do a meridian flip that I totally wasn’t expecting.
The time until meridian flip indicator was still showing three hours or so remaining. The scope was on the west side of the mount, pointing east, but still had not reached the meridian. Indeed it visually looked like the scope had a good distance to go before even reaching the merdian, much less flipping, and the CGE Pro is supposed to be able to track a full 20° past the meridian, something that looks plausible given my tube length and physical configuration.
Here are my software versions, an excerpt from my logs around the suspicious event, and the entirety of the logs in case my excerpt is a red herring:
SGP: 2.4.1.10
CGE Pro HC firmware: 4.21
CGE Pro MC firmware : 6.09
NexRemote: 1.7.22
NexRemote DLL: 1.7.2
Grepping the logs for hour angle checks I see the following over my session:
[7/3/2015 10:32:59 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -71.2389993667603 < 15
[7/3/2015 10:43:43 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -68.537929058075 < 15
[7/3/2015 10:49:17 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -67.1451759338379 < 15
[7/3/2015 11:04:24 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -63.3678531646729 < 15
[7/3/2015 11:10:56 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -61.7128872871399 < 15
[7/3/2015 11:16:29 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -60.3208637237549 < 15
[7/3/2015 11:22:04 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -58.9240121841431 < 15
[7/3/2015 11:27:36 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -57.5371170043945 < 15
[7/3/2015 11:33:09 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -56.1466383934021 < 15
[7/3/2015 11:38:42 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -54.7569966316223 < 15
[7/3/2015 11:44:15 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -53.3662819862366 < 15
[7/3/2015 11:49:47 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -51.9791722297668 < 15
[7/3/2015 11:55:20 PM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -50.5944871902466 < 15
[7/4/2015 12:00:54 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -49.2006182670593 < 15
[7/4/2015 12:06:27 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -47.8102040290833 < 15
[7/4/2015 12:12:02 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -46.4106702804565 < 15
[7/4/2015 12:17:35 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -45.017101764679 < 15
[7/4/2015 12:23:08 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -43.6292624473572 < 15
[7/4/2015 12:28:40 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -42.2406721115112 < 15
[7/4/2015 12:34:13 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -40.853111743927 < 15
[7/4/2015 12:39:46 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -39.4609594345093 < 15
[7/4/2015 12:45:18 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -38.0731201171875 < 15
[7/4/2015 12:50:52 AM] [DEBUG] [Sequence Thread] Meridian Flip not needed, Hour Angle < Degrees Past To Flip: -36.6774272918701 < 15
[7/4/2015 12:56:27 AM] [DEBUG] [Sequence Thread] Meridian Flip needed, Hour Angle >= Degrees Past To Flip: 45.7921957969666 >= 15
The unexpected flip attempt seems to go with the last check where, after just 5 minutes have elapsed we suddenly see hour angle jump from -36.67° to 45.79°! At that moment, the meridian flip UI window pops up and the system starts going through the process generating logs as follows:
[7/4/2015 12:56:27 AM] [DEBUG] [Sequence Thread] Checking if Meridian Flip is needed
[7/4/2015 12:56:27 AM] [DEBUG] [Sequence Thread] Telescope is on the West side of the mount
[7/4/2015 12:56:27 AM] [DEBUG] [Sequence Thread] Meridian Flip needed, Hour Angle >= Degrees Past To Flip: 45.7921957969666 >= 15
[7/4/2015 12:56:27 AM] [DEBUG] [Sequence Thread] Running blocking meridian flip…
[7/4/2015 12:56:27 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Starting Meridian Flip Procedure
[7/4/2015 12:56:27 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Calling SGM_TELESCOPE_SOLVE
[7/4/2015 12:56:27 AM] [DEBUG] [Pier Flip Thread] Meridian flip: Waiting for scope solve to complete…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] SGM_TELESCOPE_SOLVE message received…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] Telescope solve with plate solver Astrometry.NET…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] Setting filter for scope sync…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] Setting filter position 5…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] Filter position 5 is already set. Skipping…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] Plate solving scope frame…
[7/4/2015 12:56:27 AM] [DEBUG] [Telescope Thread] Created full file name (file does not exist): C:\Users\Jerry\AppData\Local\SequenceGenerator\Temp\plate_solve_image.fit
[7/4/2015 12:56:27 AM] [DEBUG] [Camera Thread] SGM_CAMERA_PLATE_SOLVER_CAPTURE message received…
[7/4/2015 12:56:27 AM] [DEBUG] [Camera Thread] Collecting FITs headers for plate solve frame…
[7/4/2015 12:56:27 AM] [DEBUG] [Camera Thread] Collecting FITs headers for plate solve frame…
[7/4/2015 12:56:28 AM] [DEBUG] [Camera Thread] SBIG Camera: CaptureImage…
[7/4/2015 12:56:28 AM] [DEBUG] [Camera Thread] SBIG Camera: Start exposure…
[7/4/2015 12:56:28 AM] [DEBUG] [Camera Thread] SBIG Camera: exposure time = 200
[7/4/2015 12:56:28 AM] [DEBUG] [Camera Thread] SBIG Camera: shutter is open…
[7/4/2015 12:56:28 AM] [DEBUG] [Camera Thread] SBIG Camera: capture command sent…
[7/4/2015 12:56:30 AM] [DEBUG] [Camera Thread] SBIG Camera status check: INTEGRATING
[7/4/2015 12:56:31 AM] [DEBUG] [Camera Thread] SBIG Camera status check: INTEGRATION_COMPLETE
[7/4/2015 12:56:32 AM] [DEBUG] [Camera Thread] SBIG Camera: end exposure called…
[7/4/2015 12:56:32 AM] [DEBUG] [Camera Thread] SBIG Camera: read data…
[7/4/2015 12:56:32 AM] [DEBUG] [Camera Thread] SBIG Camera: starting readout…
[7/4/2015 12:56:32 AM] [DEBUG] [Camera Thread] SBIG Camera: reading lines…
[7/4/2015 12:56:45 AM] [DEBUG] [Camera Thread] SBIG Camera: end readout…
[7/4/2015 12:56:45 AM] [DEBUG] [Camera Thread] SBIG read complete. Took 13590ms…
[7/4/2015 12:56:45 AM] [DEBUG] [Camera Thread] Created full file name (file does not exist): C:\Users\Jerry\AppData\Local\SequenceGenerator\Temp\plate_solve_image.fit
[7/4/2015 12:56:45 AM] [DEBUG] [Camera Thread] ---------> Save file took 122ms
[7/4/2015 12:56:45 AM] [DEBUG] [Camera Thread] SGM_CAMERA_PLATE_SOLVER_CAPTURE complete…
[7/4/2015 12:56:46 AM] [DEBUG] [Telescope Thread] Astrometry.NET convertedAstrometry.fits path: C:\Users\Jerry\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits
[7/4/2015 12:56:46 AM] [DEBUG] [Telescope Thread] Astrometry.NET - File is too large, resizing
[7/4/2015 12:56:46 AM] [DEBUG] [Telescope Thread] Astrometry.NET - Saving file
[7/4/2015 12:56:46 AM] [DEBUG] [Telescope Thread] Astrometry.NET using endpoint: http://127.0.0.1:8787/api/
[7/4/2015 12:56:46 AM] [DEBUG] [Telescope Thread] Astrometry.NET - Calling Async Solve
[7/4/2015 12:56:46 AM] [DEBUG] [Unknown] Astrometry.NET uploading file: C:\Users\Jerry\AppData\Local\SequenceGenerator\Temp\convertedAstometry.fits
[7/4/2015 12:57:01 AM] [DEBUG] [Main Thread] PopulateDataModel: Transferring view to the data model…
[7/4/2015 12:57:01 AM] [DEBUG] [MF Update Thread] Performing serialize…
[7/4/2015 12:57:14 AM] [DEBUG] [Unknown] Astrometry.NET - Upload complete
[7/4/2015 12:57:14 AM] [DEBUG] [Unknown] Astrometry.NET - Waiting for solve to complete
[7/4/2015 12:57:15 AM] [DEBUG] [Unknown] Astrometry.NET - Job successfully solved
[7/4/2015 12:57:15 AM] [DEBUG] [Unknown] Astrometry.NET solve done in 28 seconds.
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Astrometry.NET - Solve Completed
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Astrometry.NET - Solve Successful
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Plate solving scope frame successful, scope is synced, writing FITs header info…
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Checking to see if solve might be bad…
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] User chose to abort sequence due to bad solve…
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Telescope: Syncing to J2000 RA: 20.935787137 Dec: 31.6688313349
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Telescope Sync: Passed in J2000 but mount requires JNOW, converting…
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Telescope: Syncing to JNOW RA: 20.9469547808002 Dec: 31.7298302469482
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Attempting to write fits header info for
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] Scope solve complete…
[7/4/2015 12:57:16 AM] [DEBUG] [Telescope Thread] SGM_TELESCOPE_SOLVE message complete…
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Meridian flip: Scope solve complete…
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Solve and Sync was Successful
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Stopping the Auto Guider
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Attempting to stop PHD2 guiding…
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Checking PHD2 state…
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] PHD2 GetPhdStatus - Pre-Wait : Guiding
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Sending to PHD2:
{“method”: “get_app_state”, “id”: 1001}
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] PHD2 GetPhdStatus - Post-Wait: Guiding
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Sending to PHD2:
{“method”: “stop_capture”, “id”: 1004}
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Checking PHD2 state…
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] PHD2 GetPhdStatus - Pre-Wait : Guiding
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Sending to PHD2:
{“method”: “get_app_state”, “id”: 1001}
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] PHD2 GetPhdStatus - Post-Wait: Stopped
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] PHD2: Successfully stopeed PHD2…
[7/4/2015 12:57:16 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Sending Telescope command to execute meridian flip
[7/4/2015 12:57:17 AM] [DEBUG] [Telescope Thread] ASCOM Telescope: Pier side is West
[7/4/2015 12:57:17 AM] [DEBUG] [Telescope Thread] ASCOM Telescope: attempting pier flip using sideOfPier
[7/4/2015 12:57:17 AM] [DEBUG] [Telescope Thread] Setting Pier East
[7/4/2015 12:57:17 AM] [DEBUG] [Telescope Thread] Pier Flip failed when using side of pier: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. —> System.Runtime.InteropServices.COMException: Setting the side of pier to East cannot be done because the current position cannot be reached with the mount on that side of the pier
— End of inner exception stack trace —
at System.RuntimeType.InvokeDispMethod(String name, BindingFlags invokeAttr, Object target, Object args, Boolean byrefModifiers, Int32 culture, String namedParameters)
at System.RuntimeType.InvokeMember(String name, BindingFlags bindingFlags, Binder binder, Object target, Object providedArgs, ParameterModifier modifiers, CultureInfo culture, String namedParams)
at System.Type.InvokeMember(String name, BindingFlags invokeAttr, Binder binder, Object target, Object args, CultureInfo culture)
at ASCOM.DriverAccess.MemberFactory.CallMember(Int32 memberCode, String memberName, Type parameterTypes, Object parms) in c:\ASCOM Build\Export\ASCOM.DriverAccess\MemberFactory.cs:line 331
[7/4/2015 12:57:46 AM] [DEBUG] [Main Thread] PopulateDataModel: Transferring view to the data model…
[7/4/2015 12:57:46 AM] [DEBUG] [MF Update Thread] Performing serialize…
[7/4/2015 12:57:48 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Telescope command to meridian flip has completed
[7/4/2015 12:57:48 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Telescope failed to perform meridian flip
[7/4/2015 12:57:58 AM] [DEBUG] [Pier Flip Thread] Meridian Flip: Procedure complete
[7/4/2015 12:58:02 AM] [DEBUG] [Sequence Thread] Blocking Pier Flip: Failed to meridian flip, aborting sequence (False)
[7/4/2015 12:58:03 AM] [DEBUG] [Sequence Thread] SBIG Camera: end exposure called…
[7/4/2015 12:58:03 AM] [DEBUG] [Sequence Thread] SBIG Camera: end readout…
[7/4/2015 12:58:03 AM] [DEBUG] [Sequence Thread] Run event requested sequence abort…
[7/4/2015 12:58:03 AM] [DEBUG] [Sequence Thread] Clearing timed monitoring events…
[7/4/2015 12:58:03 AM] [DEBUG] [Sequence Thread] Checking RunEndOfSequenceEquipmentOptions, force = False
[7/4/2015 12:58:03 AM] [DEBUG] [Sequence Thread] Sequence was aborted, skipping end of sequence options…
If I’m interpreting the above correctly, it seems that SGP asked the mount to perform a meridian flip, and the mount rightly refused since it couldn’t go from the “scope on the West pointing East state” to the “scope on the East still pointing East,” which makes sense since the OTA still hadn’t reached the meridian and looking at the physical configuration of the scope while this was going on showed it to be impossible.
Any suggestions? Did I do something to bring this on myself via misconfiguration of either SGP or the connected gear? I was fussing about the laptop desk at the time this happened, but AFAIK I hadn’t touched the keyboard or mouse. My first thought when the meridian flip window came up was that I’d trigged it myself, but I’m having trouble guessing what I might have done that would have caused the sudden hour angle leap we see above.
I’ve not actually done a meridian flip with this gear configuration yet, and had been hoping to save that for a night of drill and practice dedicated to meridian flipping sometime in the next few days. I’ll definitely be trying deliberate meridian flips next time I get out. In the meantime, if anybody has any pointers, I’m all ears.
Beyond the surprise meridian flip though, the night of imaging was great. The SGP/PHD2 combo in my current configuration performed otherwise beautifully and it was faster to get started than any night so far.sg_logfile_20150703220406.txt (569.6 KB)