RCC Newby looking for advice on my IC63

andrea tasselli:
Apart from the poor flat field (very poor), the exceedingly large spikes (magenta?) and the poor star colours how on earth did you manage to get the main emssion nebula yellow? I mean, you get red (from H-a) and blue+green (from OIII) you should go for a HOO composition.

That's a bit rough...

The first issue I would work on is the flat field correction.
You can try to remove it with DBE in PI:
place a sample in the middle of the light ring and then in the symmetries section of DBE for that sample select Axial and increase the value to get a shape that will match the one of the light ring, you can move the sample in or out to match the light ring radius. Then place a few more inside and out the ring in places where there's no light ring, with the same symmetry settings. DBE should match the doughnut gradient and remove it.
The better solution would be to fix your flat calibration to it will properly flatten the field, when you see circular light rings it means the calibration was not successful and you're either under or overcorrecting the flats. Adam Block has a few nice videos on youtube on this topic. Common problems that cause incorrect flat field calibration are:
- improperly calibrating the flat fields with bias or darkflat frames
- outdated or mismatched dark frames (wrong gain or outdated darks)
- things like light leaks while capturing the image or the calibration frames can derail the calibration process
- internal reflections from filter, adapter, etc.
It is very important to be able to properly calibrate your frames so you should invest enough time to perfect that process (took me months to be able to get reliable results).

Color is a bit subjective, so are spikes. The advice others offered are very good starting points. IC63 can be a bit tricky as it's both a reflection and emission nebula so it's not easy to reproduce its usual colors only with narrowband data, as you get from the L-extreme. You might try capturing it with a luminance filter on a moonless night, you might get better colors to start with.

This is not an object that is suited for Hubble palette… but that’s your choice. 

As for the star reduction, there are much better ways to do this. Looks like you used morphological transformation here multiple times each iteration further degrading the stars. It’s a tool I stopped using early on. It works alright for one or two iterations with a good starmask but it’s an inferior method. Starnet and pixel-math are something to look into To remove stars and put them back in. 

Remember the more you do to your image the further you degrade it. Some people call that art but most times it’s butchery.

Thanks,  best hobble I've ever been a part of.