M31-first attempt

[dark star]

Hi, I finally got my Canon 20D DSLR to focus with my Orion Optics UK 250mm f4.8 reflector by fitting longer

collimation bolts and so moving the mirror further up the tube. A lot of 40 second exposures as I was using these to try to get good focus, a small number of 60 second and 90 second exposures. Using APT, Astrophotography Tool.

There is some vignetting, I haven't figured out darks yet, I will give them a try at some point. Stacked in DSS Deep Sky Stacker and processed in Photoshop. The first Drop box link is to the stacked images before processing, the second after processing. There was a full moon which didn't help, I will try again with more and longer exposures when there isn't a full moon. I am waiting for a Baader MPCC coma corrector, which should improve things. I will also try my Atronomik CLS clip light pollution filter. Any advice welcome.

David

https://dl.dropbox.com/u/82184859/M314th.TIF

https://dl.dropbox.com/u/82184859/M31best.tif

[dark star]

Hi, the TIFF files take quite a long time to download, so I have attached a JPEG file.

David

[Ganymede12]

Better than anything I have so far. I think I can see a bit of star trailing so you may need to work on the tracking. Other than that it looks great.

[ollypenrice]

You need flats. The bright inner circle is caused by the uneven illumination of the telescope which is perfectly normal but which flats would correct, leaving the rest of the processing much more coherent.

Olly