Does stacking multiple stacks yield the same result as creating one stack of the total number of frames? For example, suppose that I create a live stack of 100 frames tonight and save as a 16-bit FITS file one evening, then create a live stack of 200 frames of the same image on another night. If I then used Deep Sky Stacker to stack the two stacks into one stack, is the resulting final stack the same result as one 300-frame stack?
What I'm wanting to do is to get data over multiple nights but avoid having to save all of the individual frames and stack the large group later.
Thanks,
Mark
Stacking Multiple Stacks?
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Re: Stacking Multiple Stacks?
Hi Dave, I don't believe that the link that you referred me to answers the question.
thanks,
Mark
thanks,
Mark
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Re: Stacking Multiple Stacks?
Hi,
If all your stacks are the same length then the answer is yes. If your stacks are different lengths then I suspect it may be hard to persuade deep sky stacker to give additional weight to the longer stacks in the way that it should, which will mean that some of the additional detail that should be visible in the longer sub stacks won't be given the weight it deserves in the final image.
Cheers, Robin
If all your stacks are the same length then the answer is yes. If your stacks are different lengths then I suspect it may be hard to persuade deep sky stacker to give additional weight to the longer stacks in the way that it should, which will mean that some of the additional detail that should be visible in the longer sub stacks won't be given the weight it deserves in the final image.
Cheers, Robin
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Re: Stacking Multiple Stacks?
Excellent, thanks Robin!
Mark
Mark
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Re: Stacking Multiple Stacks?
I can report that stacking multiple live stacks in Siril works just fine. I don't know whether it weighted the images by integration time, and can't say that I really much care as the stacks were all 3-4 hours.
I was primarily interested in tracking the very faint stars around the M51 A&B pairs of galaxies (NGC 5194 and 5195). The negative I made from the resultant picture shows that I was more successful than I had hoped for a total of 15 hours exposure.
(11" SCT, 0.63x reducer/corrector, ZWO ASI2600MC, four live stacks in SharpCap, Siril for overall stack, photometric colour calibration, etc, and Gimp for final processing.
I was primarily interested in tracking the very faint stars around the M51 A&B pairs of galaxies (NGC 5194 and 5195). The negative I made from the resultant picture shows that I was more successful than I had hoped for a total of 15 hours exposure.
(11" SCT, 0.63x reducer/corrector, ZWO ASI2600MC, four live stacks in SharpCap, Siril for overall stack, photometric colour calibration, etc, and Gimp for final processing.
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Re: Stacking Multiple Stacks?
Hi,
that's quite a different approach to the processing, but *very* striking - you could imagine that you are looking at a pair of black holes!
Glad to hear that the stacking worked as expected.
cheers,
Robin
that's quite a different approach to the processing, but *very* striking - you could imagine that you are looking at a pair of black holes!
Glad to hear that the stacking worked as expected.
cheers,
Robin
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Re: Stacking Multiple Stacks?
Hi Robin,
I nicked the idea from the way they used to show galaxies in the era of photographic glass plates. Arp's 1966 Atlas of Peculiar Galaxies is available for free online, and that's the way the galaxies are presented there. See e.g. http://ned.ipac.caltech.edu/level5/Arp/Arp22.html
Regards,
Jane.
I nicked the idea from the way they used to show galaxies in the era of photographic glass plates. Arp's 1966 Atlas of Peculiar Galaxies is available for free online, and that's the way the galaxies are presented there. See e.g. http://ned.ipac.caltech.edu/level5/Arp/Arp22.html
Regards,
Jane.