Stacking the data of multiple nights

@yellowhorsehead Hi Andi. Do you reuse the calibration data (most notably the flats) for all nights? If yes, you can split up all data in batches of, say, 100 and then in the end load all integration results as lights (don't load any calibration data) and integrate those. 

If you have flats for each night you can process per night. If there are too many subs in a single night then you can split that up as described above. In the end you can again load all integration results as lights (again without calibration data) and stack those. 

@wvreeven Just adding to this thread, so I process my nightly subs with their calibration frames and get the output fit file.

So I then load these all as lights and just integrate them. Do I need to change any setting from the default? (I'm shooting M51 with about 40 subs per night with exposures of 15s,50s 90s etc (Newbie and just sorting mount, tracking and guiding, so getting better.......) 

@hookandy There shouldn't be a need to change the defaults, unless you get a mono integration result where you expect a color one. In that case you need to tweak the settings in tab 0.