Help with M31 - pretty please.

[earth titan]

Just getting started and hoping for some pointers. I've posted the final processed file (image processed in trial version of nebulosity hence lines) and a .jpg version of one of the RAWs. I think the alignment is okay but not sure about the focus - but I'll await constructive comments on these matters.

Set up as follows:

Canon 1000d with astronomica CLP filter

80mm refractor

EQ5 with RA drive

23 off RAW lights ISO 1600 @ 2 minutes exposure

A couple of darks, bias and flat frames

Any hints with the kit I have?

I think less ISO (about 800) to keep the noise down, improve the focus, then see what happens.

[MartinB]

The focus is slightly off, that is the main problem. Also, are you using curves as well as levels to stretch the histogram. The core is a little burnt out and a bit of star bloat. Your polar alignment looks good since your stars are a reasonable shape.

[Moonshane]

it never ceases to amaze me how someone can take (with utter respect) a somewhat dim and detail free image and drag the data kicking and screaming out into what looks like a pretty good image!

[earth titan]

The core is a little burnt out and a bit of star bloat. Your polar alignment looks good since your stars are a reasonable shape.

Thanks Martin. If I drop the ISO down, will this help with the core and star bloating?

Then more data I'm guessing....

[JohnnyD333]

I agree with the focus issue, just adjust it with the live view on your camera on a very bright star. You are using a CLP filter on a very bright DSO, how bad is the light pollution in your area? At 1600 ISO your images should be much brighter than your single sub, the filter could be dimming your images. M31 is a tricky DSO as mentioned, its so big and bright that you will have to experiment with your ISO and exposure settings. Honestly, my best images of M31 are at ISO 3200 1 minute subs stacked. This is the complete opposite of my usual imaging settings, but it works for me for some reason.

[earth titan]

Pretty bad lp. I live in a town centre and anything over a minute is brown