Combining data from two different nights

[mikey2000]

Just a quick Q...

 

I have some subs of the Bubble Nebula from two different nights.  The first night was with the moon just creeping above the horizon (3 min subs) and the second night was no-moon and 5 min subs.  They are nicely aligned as I position the scope with plate-solving.

 

What's the best way to combine these?  I use DSS for my raw file stacking then Startools to stretch/process.  I also have Photoshop for finishing touches.

 

Thanks!

[John78]

So you can stack them all together in groups in DSS but use the same reference frame throughout to get them to stack/overlay properly - there is group tabs at the bottom of the picture file list

 

edit: using groups also lets you load calibration frame specific to each of the days also obviously

[spillage]

Also if you dither then you may be able to ditch darks which are the only calibration frames that are time/temp specific to your lights.

[mikey2000]

Good stuff.  I found the Groups tab now.

 

do I need to worry about any of the Background Calibration options?  I'm not 100% sure what they are for.   Is it anything to do with handling the different night sky backgrounds for each set? (With the moon a little bit up, the suns are slightly more grey looking compared to the moonless suns, which appear blacker overall)