Saturday 30 April 2016

Galaxy Quest

At last, an image of M101. This is a quick and dirty stack of six ten minute sub-frames, aligned using Photoshop. There is a lot of electronic noise in the frames which I would like to remove.

A pass through confirms the pointing:

And here's a crop, with some contrast tweaking, of the galaxy itself:

The string of stars in the lower left corner (and elsewhere) is the result of individual hot pixels being shifted and duplicated as I did the manual alignment. This is the kind of electronic noise which I'd like to remove when I get a bit more time.


  1. Nice work!

    This is the thing I find so frustrating with astrophotography. I see the stunning photos from other amateur astronomers and think, "I can do that!" Then spend many hours freezing my bits off at the telescope and more time wrestling with software post-processing my images and the best I can come up with is some fuzzy blobs that might look like something vaguely interesting if you squint the right way. Then I pack up the telescope and don't bother getting it out for another six months.

  2. Nice, that noise will come right out with a standard deviation intensity cutoff during stacking. However, doing a complete astrophotography workflow in photoshop requires a lot of effort. I would suggest getting Nebulosity (, which is one of the easier astrophotography softwares out there. An alternative is Pixinsight (, which is amazing but has a steeper learning curve.

  3. Thanks - good tips. I do have Nebulosity, but I've barely scratched what it can do. Mostly just used it for controlling the image capture so far.

  4. Can Nebulosity control capture!? *mind blown*. I have to look into that.

  5. Yes, and it's much less clunky than the control software that came with my camera. It also has many, many cameras built into its library so all I have to do is scroll down and select mine.