It is already my third attempt to this object 🙂 I really do not feel comfortable with processing of this magnificent galaxy, I always have a feeling it can and should be done better. Maybe one important factor is sky quality, and I need to collect photons under some decent and dark sky, not at my suburban backyard.
Anyway – this one is probably well known to all astronomy lovers. That is Messier 33 spiral galaxy in Triangulum. It is large, apparently as large as Moon, so it also means this galaxy is pretty “close” to us. As close as about 3 millions light years. M33 contains also many HII active regions. Some of them are visible at the picture below as magenta clouds. But I have not gathered narrowband H alpha data, so these regions do not manifest clearly.
Picture has been made with 130mm refractor and QHY163M camera using Baader LRGB filters. It is total 6h of luminance and 2h of RGB signal.