I have about 2h of images on the whirlpool galaxy that I've put into deep sky stacker, all of similar quality to the 1 below (biases, darks and flats provided, the picture below is untouched). When trying to stack the alignment is dreadful and everything is blurred when viewing it in photoshop with an increased exposure. Why would this be? I have read that only 8 stars are needed for an alignment - around the galaxy itself I can make out 10 on the raw unreduced data. Maybe focus related? although I think strong enough. Isolating the best images with little trailing and stacking in DSS doesn't improve things either.
Equipment and settings:
Camera - Nikon D3500, ISO 6400, 30s exposure, white balance auto, raw format
Telescope stuff - EQ5 goto (~15arcmin accuracy on goto, target is kept in a similar position throughout observations with little trailing), Skywatcher explorer 200P with a 2x barlow
DSS - recommended settings, stacking parameters are median/kappa-sigma clipping (default values) for everything, alignment neither automatic or billinear. 2% detection with hot pixels searched for gives about 50 stars, 3% about 5-10 across the whole bunch.
Thanks in advance!