Poor star detection behaviour in live stack

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celkins
Posts: 129
Joined: Fri Apr 20, 2018 10:58 pm

Poor star detection behaviour in live stack

#1

Post by celkins »

Robin,
please find below a snippet of the log, when Live Stack was failing to align frames, despite having aligned the previous 30...
=======================

Code: Select all

Debug  	00:43:54.693616	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	00:45:55.342050	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:45:55.343550	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	00:47:56.012487	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:47:56.013489	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	00:47:56.932975	#28	SharpCap.FrameTransforms.LiveStacking.LiveStackTransform processed frame in 919ms										in BufferFrame SharpCap.Base.BaseImageProvider.RunFrameProcessor(BufferFrame frame)
Debug  	00:49:56.657930	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:49:56.659431	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	00:51:57.286373	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:51:57.287373	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Error  	00:51:57.979364	#28	Less than 3 stars found in the frame image																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:51:57.980865	#28	Alignment failed																										in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:51:57.993367	#28	System.InvalidOperationException: Less than 3 stars found in the frame image - cannot align.
   at SharpCap.ImageProcessing.Aligner.CheckFrameStars() in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 251
   at SharpCap.ImageProcessing.Aligner.GetFrameTriangles() in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 241
   at SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(Boolean lockToScaleOne, Int32 width, Int32 height) in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 129
   at SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(ICapturedFrame frame, Boolean lockToScaleOne) in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 114
   at SharpCap.FrameTransforms.LiveStacking.LiveStackProcessor.CalculateAlignment(ICapturedFrame frame) in C:\Documents\Source Code\SharpCap\src\SharpCap\FrameTransforms\LiveStacking\LiveStackProcessor.cs:line 501				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:51:58.001364	#28	Calculating alignment in live stacking : Exception of type 'InvalidOperationException' : Less than 3 stars found in the frame image - cannot align. 
Stack Trace:   at void SharpCap.ImageProcessing.Aligner.CheckFrameStars() in C:/Documents/Source Code/SharpCap/src/SharpCap.ImageProcessing/Aligner.cs:line 251
   at List<Triangle<StarInfo>> SharpCap.ImageProcessing.Aligner.GetFrameTriangles() in C:/Documents/Source Code/SharpCap/src/SharpCap.ImageProcessing/Aligner.cs:line 241
   at Matrix3x3? SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(bool lockToScaleOne, int width, int height) in C:/Documents/Source Code/SharpCap/src/SharpCap.ImageProcessing/Aligner.cs:line 129
   at Matrix3x3? SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(ICapturedFrame frame, bool lockToScaleOne) in C:/Documents/Source Code/SharpCap/src/SharpCap.ImageProcessing/Aligner.cs:line 114
   at bool SharpCap.FrameTransforms.LiveStacking.LiveStackProcessor.CalculateAlignment(ICapturedFrame frame) in C:/Documents/Source Code/SharpCap/src/SharpCap/FrameTransforms/LiveStacking/LiveStackProcessor.cs:line 501			in DisposableFrame SharpCap.FrameTransforms.LiveStacking.LiveStackProcessor.CalculateNetFrame(ICapturedFrame rawFrame, Matrix3x3? subtractAlignment)
Error  	00:51:58.001864	#28	Failed to calculate alignment.																							in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	00:51:58.004863	#28	Frame not stacked because : Could not align																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Debug  	00:53:57.919810	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:53:57.920811	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Error  	00:53:58.579301	#28	Less than 3 stars found in the frame image																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:53:58.579802	#28	Alignment failed																										in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:53:58.580802	#28	System.InvalidOperationException: Less than 3 stars found in the frame image - cannot align.
   at SharpCap.ImageProcessing.Aligner.CheckFrameStars() in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 251
   at SharpCap.ImageProcessing.Aligner.GetFrameTriangles() in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 241
   at SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(Boolean lockToScaleOne, Int32 width, Int32 height) in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 129
   at SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(ICapturedFrame frame, Boolean lockToScaleOne) in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 114
   at SharpCap.FrameTransforms.LiveStacking.LiveStackProcessor.CalculateAlignment(ICapturedFrame frame) in C:\Documents\Source Code\SharpCap\src\SharpCap\FrameTransforms\LiveStacking\LiveStackProcessor.cs:line 501				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:53:58.580802	#28	Failed to calculate alignment.																							in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	00:53:58.582802	#28	Frame not stacked because : Could not align																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Debug  	00:55:58.557260	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:55:58.558761	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Error  	00:55:59.242751	#28	Less than 3 stars found in the frame image																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:55:59.243250	#28	Alignment failed																										in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:55:59.244251	#28	System.InvalidOperationException: Less than 3 stars found in the frame image - cannot align.
   at SharpCap.ImageProcessing.Aligner.CheckFrameStars() in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 251
   at SharpCap.ImageProcessing.Aligner.GetFrameTriangles() in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 241
   at SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(Boolean lockToScaleOne, Int32 width, Int32 height) in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 129
   at SharpCap.ImageProcessing.Aligner.GetAlignmentMatrix(ICapturedFrame frame, Boolean lockToScaleOne) in C:\Documents\Source Code\SharpCap\src\SharpCap.ImageProcessing\Aligner.cs:line 114
   at SharpCap.FrameTransforms.LiveStacking.LiveStackProcessor.CalculateAlignment(ICapturedFrame frame) in C:\Documents\Source Code\SharpCap\src\SharpCap\FrameTransforms\LiveStacking\LiveStackProcessor.cs:line 501				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Error  	00:55:59.244251	#28	Failed to calculate alignment.																							in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	00:55:59.248250	#28	Frame not stacked because : Could not align																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Debug  	00:57:59.192202	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:57:59.193203	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Error  	00:57:59.896694	#28	Less than 3 stars found in the reference image																			in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	00:57:59.896694	#28	Failed to align with the reference frame.																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Error  	00:57:59.897193	#28	Failed to calculate alignment.																							in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	00:57:59.899695	#28	Frame not stacked because : Could not align																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Debug  	00:59:59.838140	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	00:59:59.839638	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Error  	01:00:00.532631	#28	Less than 3 stars found in the reference image																			in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	01:00:00.533130	#28	Failed to align with the reference frame.																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Error  	01:00:00.533130	#28	Failed to calculate alignment.																							in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.SendToMainLogger(LoggingEvent loggingEvent)
Warning	01:00:00.535631	#28	Frame not stacked because : Could not align																				in void SharpCap.FrameTransforms.LiveStacking.LiveStackViewModel.DoAppend(LoggingEvent loggingEvent)
Debug  	01:00:00.536131	#1 	Notification (Status=Warning): Warning: Last 5 frames have not been stacked, because: Could not align					in void SharpCap.UI.NotificationViewModel.DisplayMessage(NotificationMessage message)
Info   	01:01:11.735206	#39	Event received from PHD2 : ConfigurationChange																			in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Info   	01:01:12.086704	#39	Event received from PHD2 : GuideStep																					in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Debug  	01:02:00.484570	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:02:00.486071	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	01:04:01.124005	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:04:01.125005	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	01:06:01.749443	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:06:01.750444	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	01:08:02.368378	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:08:02.369379	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Info   	01:08:36.728933	#17	Event received from PHD2 : ConfigurationChange																			in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Info   	01:08:37.056928	#17	Event received from PHD2 : GuideStep																					in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Debug  	01:10:02.998823	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:10:02.999824	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Info   	01:10:17.126143	#1 	Toolbar/Menu input : SharpCap.ViewModels.Actions.ShowLogAction  executing												in async Task SharpCap.ViewModels.UIAction.Execute()
Info   	01:10:17.321139	#1 	Toolbar/Menu input : SharpCap.ViewModels.Actions.ShowLogAction  complete												in async Task SharpCap.ViewModels.UIAction.Execute()
Debug  	01:12:03.664266	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:12:03.665767	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	01:14:04.280709	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:14:04.282210	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	01:16:04.898157	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:16:04.899159	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Debug  	01:18:05.565101	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:18:05.566602	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Info   	01:18:11.762523	#32	Event received from PHD2 : ConfigurationChange																			in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Info   	01:18:12.233515	#32	Event received from PHD2 : GuideStep																					in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Debug  	01:20:06.178552	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:20:06.179553	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
Info   	01:20:49.336991	#21	Event received from PHD2 : ConfigurationChange																			in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Info   	01:20:49.680989	#21	Event received from PHD2 : GuideStep																					in void SharpCap.Base.Guiding.Phd2Api.ProcessNotification(EventBase typedEvent)
Debug  	01:22:06.841493	#27	Finished ZWO Exposure of 120000ms, gotFrame = True																		in bool SharpCap.Cameras.ASI.ASICameraProxy.GetFrameData(int timeout, BufferFrame frame, CancellationToken cancellationToken)
Debug  	01:22:06.842993	#27	Starting ZWO Exposure of 120000ms																						in bool SharpCap.Cameras.ASI.ASICameraProxy.StartExposure()
=======================

I was able to re-start stacking by increasing 'sensitivity' 76 => 78 resulting in 200+ stars, but still no FWHM...
Resetting to DEFAULTs in the ALIGN tab did result in stacked and FWHM scored frames.
Please find attached a non-stacked, non-FWHM frame, with "Highlight Detected Stars", showing stars found, but no FWHM calculated...

It just seems odd...

Carl
Attachments
Screenshot 2021-12-02 010946-FWHM-NaN.jpg
Screenshot 2021-12-02 010946-FWHM-NaN.jpg (842.77 KiB) Viewed 332 times
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admin
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Re: Poor star detection behaviour in live stack

#2

Post by admin »

Hi,

well I can solve one mystery fairly easily - that is the one of the missing FWHM values.

Stars with peak brightness near to full camera saturation do not get assigned an FWHM value. That's because there can be no confidence in that value, after all, maybe the peak brightness of the star should have been 250% of the full camera saturation, but it got limited by the FWD of the camera. In this particular case it looks like all of the 40 or so stars that are being detected are at or very near to full saturation, so none of them get an FWHM assigned. Of course those bright stars are perfectly adequate for alignment, just not for measuring image quality.

Now, as to why some frames get no stars detected suddenly, that's harder to tell without seeing the individual frame that caused the problem. I guess there must have been something fairly odd about them to go from lots of stars to less than 3.

cheers,

Robin
celkins
Posts: 129
Joined: Fri Apr 20, 2018 10:58 pm

Re: Poor star detection behaviour in live stack

#3

Post by celkins »

Thanks for that, Robin… it should have occurred to me, but it was getting late 😉🤦‍♂️

I guess it could have been thin high cloud on the leading edge of the front moving down - within the next hour or so, heavy cloud drifted in and curtailed the session.

Thanks again,
Carl
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