Can Live Stack Work With Short Exposures?

Discussions of Electronically Assisted Astronomy using the Live Stacking feature.
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Can Live Stack Work With Short Exposures?

Post by Zubenelgenubi »

I have been trying to use the Live Stack feature to image Comet Neowise. I have been using exposure between 2-4 seconds. The SharpCap FWHM focusing aid works on the background stars but Live Stack will not stack images. At first I thought that the short frames were not giving the stacking algorithm enough time to detect stars and align the frame but I cannot get Live Stack to stack even when I replay the captured frames using Folder Camera Monitor. By the way the FWHM works with the Folder Camera data. What is going on?
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Re: Can Live Stack Work With Short Exposures?

Post by BlackWikkett »

Hi Zubenelgenubi

The best way to achieve this is not aligning frames. Since you're shooting in 2-4 seconds the stacking algorithm will not detect the stars needed to align the frames. Once you start Live Stacking in the lower right uncheck Align Frames (see image below) this will still stack and should have a good result at such short expsures. I'd save after a few frames then reset as the comet is moving quite fast and If you wait to long to save the shot you'll get some smearing.
SC-alignLS.png (15.31 KiB) Viewed 474 times
good luck, Chris
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Re: Can Live Stack Work With Short Exposures?

Post by cuivenion »

You could try increasing the gain so that more stars are picked up or go to the align tab and playing with the settings to see if you can get better results.
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Re: Can Live Stack Work With Short Exposures?

Post by admin »


careful adjustment of the alignment settings may be the answer to this problem – bring up the alignment tab in live stacking and check the box to highlight the stars that are being detected. Then you can change the star detection parameters to hopefully ensure that at least 10 stars detected in each frame which should give a very good chance of alignment and stacking working.

Probably the best way to start is to reset all the parameters to their default using the 'reset all' button and then try adjusting either the black level downwards or applying a 2× digital gain to see if that helps.

Cheers, Robin
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