Stacking multiple stacks

[Ronald]

Is therr any way of stacking two separate stacks with sharpcap to get more integration time

[turfpit]

You can stack the stacks with a 3rd party app. This https://www.astrobin.com/330099/ was 5 stacks each of 30 minutes using 30s exposures. Read the comments for more info.

Dave

[admin]

Hi,

yes, as Dave says you can do this in DSS or some other stacking program. One thing to remember is that you *must not* use darks/flats/bias in DSS when doing this second level stacking. If you want to use those you *must* use them in SharpCap when doing the live stacking.

thanks,

Robin

[Ronald]

Thank you for the reply, the next question is will there be anything to be gained by stacking multiple stacks?

[admin]

Hi,

yes, there should be - if you have 4 stacks (say each of 30 minutes total exposure) then stack those 4, the resulting image should have half as much noise as any of the individual images, which will make more faint detail visible.

thanks,

Robin

[Menno555]

A "just in case" side note: stacking stacks certainly gives results. But to get the best results, the stacks should best be un-processed (other then maybe auto setting like Auto Align RGB in DeepSkyStacker). So no saving of a processed stacked FITS by for example PixInsight, Siril or other propgram and then stack those.

Also, rotation of the FOV is not that much a problem but the size of the FOV itself is. Stack programs like DeepskyStacker can handle a small difference in focal length. I can for example stack sessions made with 2030mm together with stacks that are 2027mm. So it's important that the image train is the same for both stacks, that they have almost the same focal length.

Menno

[Ronald]

Thanks for the great information. Im using livestack so as Robin said. I must do darks and flats while I am livestacking. I do not use bias because my camera is a 294mc. But, I like to do my calibration frames at dusk (flats) and darks after the exposure, gain and brightness are determined for each session. The flat frames are the only variable where the setting may change slightly, will this be ok? Also if I understand correctly no post processing until after i stack them in DSS?
Thanks again!