Hi all, this is the first proper light with my friends WO FLT 132.
Its is 5hrs 40 mins of five min subs at ISO 800 Canon 60Da cooled.
The first 21 frames I had exceptionally clear skies, after that it was a bit of smoke haze and high cloud.
I think I have an issue with flats I need to resolve and there were only 10 darks.
Overall I am pleased with this scope so far.
Thanks for looking
Cheers
Graham
Last edited by graham.hobart; 22-04-2015 at 06:29 PM.
Reason: add picture
Thanks Greg- just a question-
the granular look to the background ie not smooth, is that just a facet of there being five hours of subs and being a tad over stretched? i.e will more subs make it smoother?
Or is it my processing in Star tools?
That is the colour noise of the 60Da. You can process that out by making a mask of the object and then using curves or levels to recede the background without dimming the galaxy. And yes more exposure time will smooth it out. But the Microline 8300 would show a superior result with the same exposure time. I have done many 5 hour galaxy images with a Tak BRC250 and that camera and 5 hours would be plenty for a reasonable image (not matching some of the super IQ images that are often on this site these days but still very good). That's a 10 inch RC though. 132mm APO should still do very well but will require 10-20 hours for a nice smooth noise free image.
With CDK17 at F4.5 and 77% QE SX694 I still need to get around 10 hours to get a decent result. 20 would be a whole lot nicer, super dark skies would top it off.
If that were the FLI ML8300 you would not have that noise in the background anywhere near that. That's the power of a mono sensitive CCD. Also the high cooling of the Microline helps as well although the KAF8300 seems very clean at -15C you can easily achieve -35C all year round with the ML and in Tassie probably -45 or even -50C in winter.
The Bayer matrix and interpolation of the resulting 4 coloured pixels comes at a cost of sensitivity.
The other issue you have to monitor with a DSLR is overexposing stars and they are all white with no colour. Stars are various colours and DSLRs are notorious for showing all white stars with no colour data. You seem to have retained some colour data in your stars that possibly could be brought out more. There is a slight yellow bias to the image.
nice one graham,
I have to admit it looks a lot more noisier than I would think it would especially for nearly 6 hours data... perhaps something happened with the flats or the smoke contributed...
compare to my half hour job with a non cooled dslr which is nowhere near enough time https://www.flickr.com/photos/803366...ream/lightbox/
although you have pulled more of the faint stuff out - I couldn't because of the noise. perhaps some masking techniques would help you here.
Cheers all.
Yes, I am still trying to work filter wheel and filter options for the microline. Awaiting quotes on 36mm filters though I think astrodon are out of my league just yet.
Thanks all
Rick- at five minutes this was shot above the light dome of the city and my neighbours house- anymore and I have found the subs were too much background!
In the West-towards the Mountain I can get away with ten min subs
Er, your scope now.. 
