M31 - 8 frame Mosaic; a work in progress!

[Dunmunro]

Here I used AA9's Star Atlas mosaic generation feature to produce the target coordinates for an 8 frame mosaic of M31 using my 10in F5 SCT and an ASI071 camera. I am still working on the fine details of this to produce a near seamless image. I reduced the attached image to 1/4 (25%) size to allow me to upload it. Each of the 8 frames consisted of 6 x 300sec exposures (4 hours imaging time) and I used my automatic plate solve assisted Goto/autofocus/autoguiding imaging script to operate the mount and camera.

[Dunmunro]

The two frames (8 +7) in the upper left were shot when the scope was aimed fairly low (35d altitude) and atmospheric dust seems to have effected the images. I am sure there's a way to compensate to make the image more nearly seamless but I may have to reshoot them. The original 8 frame mosaic comes in at 1.3 gigabytes when saved as a fits file!
Ok, so I normalized (add) frame 7 to the 6-frame mosaic and then did the same for frame 8 (upper left) and adjusted it's colour balance and here's the result:

[fabdev]

Thanks, in the incoming SP1 there will be two new filters to post-process uneven brightness. One is indeed for mosaics, to soften the edges, before a further background normalization. The other can be used for isolated bright and dark spots.
Here is an animation about the first one:
Fabio.