M31, Rosetta and NGC 869/884

[nmoushon]

So I was able to drive to a dark site this weekend. Well dark for where I'm at. Here's 3 of the better set of images that I was able to get. Still trying to learn all the techniques. So comments and suggestions are welcome. All exposures were taken with Canon 450D at ISO1600, f/6.3, 300mm.

M31 = 1-1min and 4-3min + darks

Rosetta = 1-1min, 3-3min and 1-5min + darks

NGC869/884 = 1-1min and 3-3min + darks

[Yoddha]

Beautiful images! Your tracking is very good - nice round stars

If you add more subs you will have lower noise and more details in the final image

[nmoushon]

Thanks Yoddha,

I got over ambitious and had a list of about 12 different DSO that I tried imaging that night lol. I'll slim it down next and concentrate more.

Question though: I noticed it during processing but forgot to but it up on original post but the stars seem to have to purple off-set halo around them. I'm not quite sure whats causing it. At first I thought it was the focus but now I dont think thats it. Its most noticeable in the double cluster image.

[Yoddha]

You are welcome!

The purple halo are aberrations from the lens. Lens are not so good as an APO refractor and usually show this "defect" which is not so obvious for day-time pictures. There are two options - to to set the lens to a lower f-stop (which leads to increasing of the exposure time) or to use software to remove the effect during the processing. The best results give the combination of both - to find the fastest f-stop that can be corrected with the software.

I use Noel's actions pack with great success when image with lens.

[Zul]

Cracking images!

[nmoushon]

Thanks again Yoddha. I'll take a look at that program later tonight. The images are set one step down already. I'll try another stop down just to see what happens.

[Sam]

They are a very nice set of images. You've achieved a good focus.

[rocketandroll]

That's a nice start :-)

Yeah, you really want to get it down to two or three targets in the night... then eventually down to one... then down to one over a few nights :-)

M31 and the Rosette will look great... but only with a couple of hours or more of data in total... though you've not done to badly for a few minutes of data!

Ben