MY NEMESIS!! Jeez, this 3.5 hours of data has given me so much grief. First galaxy with the 269c pro TEC and I'm impressed, given how far away it actually is!! Have been troubleshooting for around a week! Bad flats, bad darks, light leaks, software problems, old snail's pace laptop causing issues. Nearly gave up. I didn't, so here is Messier 101 aka The Pinwheel Galaxy 🙂 Stacked in DSS, stretched and LP removal in APP and then Photoshop.
26x240s plus darks and flats. I could've pushed the subs to 300s though.
Skywatcher 72ED, 0.8 reducer/flattener, 269c pro TEC