FLI Proline 16803,Pentax 67 75mm F4.5 at F4.5 HaLRGB image 3 x 10mins Ha 3 x red 2 x green and 3 x blue all 2x2 binning and 3 x 10mins luminance 1x1 binning. AP1600 mount piggybacked on a CDK 17 telescope.
full exif
Wow this looks amazing! What you call the Gum Nebula is actually Sh2-27 but is also catalogued as Gum 73. You have also shown hints of the 14x12 degree nebula Sivan 10 around IC 4592 and Sh2-1!!!