Stacking help

[bulrichl]

Hello Niall, yep that clears it up. Thanks also to Bernd, il try that later during the day. I took my darks and biases yesterday, but when trying to use batch preprocessing, everything works fine until it tries to integrate light frame, which it says there's insufficient signal. Anyone know why? I've tried it a few times, but get the same message every time.   

I always used longer exposure times and presumably therefore never got the error message "Zero or insignificant signal detected (empty image?)". Open the calibrated grayscale image P107021_c and inspect it with ImageInspection/Statistics ('Unclipped' must be unchecked) and IntensityTransformations/HistogramTransformation (increase Horizontal zoom until you see a peak; 50 may be a proper start value):

1) Statistics: the value of count (%) should be near 100 % (the rest is zero or negative values),
2) Histogram: the peaks should not look like cut off at the left side.

If these conditions are not met, there went something wrong with the ImageCalibration. For comparison I append a histogram and statistics of a typical calibrated image (exposure time 6 minutes).


Which were the settings used in ImageCalibration (in your case, all setting in the segments 'Master Bias' and 'Master Dark' are the relevant ones)?

Bernd

[Purplepanda]

Hello there again! So, I'll try that tomorrow, thanks! However, before seeing your reply I went ahead and did the process 'manually', in a sense. I followed the link which I'll post below. And Lo and behold, another problem, this time, there isn't any correlation between master dark and target image (light frames), so my final light frame ended up being the same as without calib

I'll do what you said in your last post, before trying other stuff. This is getting extremely frustrating  . Maybe I should just try get another data set?

https://m.youtube.com/watch?v=zU5jJgjKuQQ

Cheers!

[Niall Saunders]

. . . insufficient signal . . .

Personally, I have never seen this message, but I would suggest that you start by examining the image that had just been opened (as per the error message). Have a look at the Image Statistics for this image - is it really an 'empty' image? What does the image look like if you apply a really aggressive ScreenTransferFunction?

[Niall Saunders]

Hi 'PurplePanda' (it might be easier if you gave us an easier name to call you  ),

I just watched the video tutorial that you referred to in your last post - I hadn't seen that one, and it actually made me realise that I had been doing something wrong myself! Every day is a school day.

However, one of the linked videos was this:
https://www.youtube.com/watch?v=qduTMZ1Isa4&app=desktop#t=10.247729

I haven't watched it in full yet - but the title made me think that it might contain some helpful hints for you (assuming that you haven't already watched it!)

Anyhow - if it doesn't directly help you, it may still be of use to others who might stumble across this thread.

[Purplepanda]

. . . insufficient signal . . .

Personally, I have never seen this message, but I would suggest that you start by examining the image that had just been opened (as per the error message). Have a look at the Image Statistics for this image - is it really an 'empty' image? What does the image look like if you apply a really aggressive ScreenTransferFunction?

Hello, without the screen transfer function, I can definitely see some stars (easily more than 10). After applying the screen transfer function, I can see the Milky Way in the centre of the image. The strange thing is, I don't get this problem if I simply go to process- image integration and do it from there.

I'd love to follow the video, but have to solve this problem with the hot pixels first I guess?



Cheers,
Isaac

[Purplepanda]

1) Statistics: the value of count (%) should be near 100 % (the rest is zero or negative values),
2) Histogram: the peaks should not look like cut off at the left side.

If these conditions are not met, there went something wrong with the ImageCalibration. For comparison I append a histogram and statistics of a typical calibrated image (exposure time 6 minutes).


Which were the settings used in ImageCalibration (in your case, all setting in the segments 'Master Bias' and 'Master Dark' are the relevant ones)?

Bernd
[/quote]

 I did the statistics test, and for both conditions you said should be met, my image did not meet them  so, count(%) is 21.37% and histogram is clipped off at the left side, I only see half a peak (which is ofc the RHS of it). What. A. Bummer.

[bulrichl]

1) Statistics: the value of count (%) should be near 100 % (the rest is zero or negative values),
2) Histogram: the peaks should not look like cut off at the left side.

If these conditions are not met, there went something wrong with the ImageCalibration. For comparison I append a histogram and statistics of a typical calibrated image (exposure time 6 minutes).

Which were the settings used in ImageCalibration (in your case, all setting in the segments 'Master Bias' and 'Master Dark' are the relevant ones)?

I did the statistics test, and for both conditions you said should be met, my image did not meet them  so, count(%) is 21.37% and histogram is clipped off at the left side, I only see half a peak (which is ofc the RHS of it). What. A. Bummer.

Yes. It's not wise to try more and more different settings when you don't know at which point things go wrong - there are several possibilities. E. g. it's possible that the darks don't match the lights for some reason, or you used wrong calibration settings. But you don't get on with complainig nor speculating, you have to analyze it step by step. Fortunately, PixInsight offers all the tools to get it right. The good point is: if you have fixed it once it will not be a problem in future anymore.

Because you already have the calibrated light frames I proposed that we analyze one of your calibrated frames. So I wanted you to have a look at a calibrated image AND communicate the corresponding calibration settings. Without that information, I cannot provide further assistance. Indeed you got different error messages at the calibration trials. It is important that you can attach the error message to the corresponding calibration settings. Once more: all settings in the segments 'Master Bias' and 'Master Dark' are the relevant ones.

Bernd