M81/M82 (dusted off the old achromat......)

[stan26]

The last few of days I have been without a modded camera, but I couldn't resist the opportunity that Saturday nights weather brought us and decided that some imaging needed to be done, but I had to use my normal daytime 500D so I opted for a galaxy (or two) to image and decided on the M81 / M82 duo.

The problem is I couldn't really use my favorite 200mm L series lens, it simply doesn't have the legs for such a target, I needed something with a bit more focal length, so out came the old trusty, or should I say "dusty" ST102! I honestly can't remember the last time It saw the light of day.....er...or night?

Strapped to the HEQ5 I managed 2hrs, 2mins of data before I couldn't hack the tiredness anymore and called it a night at around 1am.

No Darks or flats, but 250 x 4000th sec BIAS frames stacked in kappa sigma mode.

Huge amount of CA to deal with, but other than this optical artifact it still impresses me what can be done with a cheapo Chinese refractor........

Stan

Galactic Duo M81 & M82 by James stannard, on Flickr

[Gina]

Beautiful - wonderful image

[Chris]

That is stunning James! It always surprises me what you (inparticular) can do with these cheap Achro's Fantastic detail and lovely colour very well processed, good to see the good old ST102 up and running again

Chris

[stem1989]

beautiful, love the colours and its a very sharp detailed image

[sologuitarist61]

Beautiful!

[nightvision]

That's very impressive even before considering it was captured with an Achro and unmodified DSLR, did you have to clean up the CA (if so what did you use)?

[planetdnb]

Nice!

[twotter]

That's a cracking image. I would put a frame round it and put it on the wall

[WhiteShiva]

Beautiful image, definitely something I want to concentrate on come next season. Imaging will soon become impossible up in the north east until after the summer. We will be loosing astronomical darkness very soon!

[stan26]

Thanks Guys, Tony- Yes the CA was really bad so it had to be cleaned up. To do this I created a separate layer in PS and de-saturated the blues and matched the lightness to match the background as best i could. The stars where still left looking very blooby so I then selected them (using colour selection tool) and used a filter in PS call "minimize" and contracted them by 1-2 pixels to bring them back down to the correct size. I then bring them through to the top layer using a layer mask, and that's the basics around the method anyway....

Cheers

Stan.

[stan26]

Slightly tweaked version, noticed a bit of a reddish gradient in the first one, and a little more noise reduction added......

Galactic Duo M81 & M82 by James stannard, on Flickr

[JamesF]

That's a lovely image and all the more impressive for being taken with the ST102.

James