If your imaging with a full spec modded DSLR then I recommend to have a read of Jerry Lodriguss’ write up on Custom White Balance for both stock and modded DSLR’s
www.astropix.com ( Using a Custom White Balance for Astrophotography)
Jerry who his one of the most regarded DSLR Astrophotographers in the US, has written the A to Z of Custom White Balance
Well worth reading
I used a stock Canon 600D for 3 years so just set an Auto White Balance AWB which was straightforward. Stacked Raw Cr files in DSS and processed in Startools, only ever took darks , no other calibration frames and my backgrounds always looked ok
Cheers
Martin