Ngc3372 - Ngc5139

[multiweb]

It's been a while since I got he scope out. I took two shots from Liverpool skies tonight. Lot of sky glow and a bit of haze but I tried different things this time. Short series (5 x) of 30 second exposures at ISO3200. I also used the Pentax *istD noise reduction and didn't use dark frames. It seems to cut down the noise better with this camera although I would need more and better data to stack.

I'll try again in two weeks time under dark skies. Photos were taken through an ED80 at prime focus - autoguided.

[Dennis]

Nice work Marc, a couple of very tidy images. What happened to the colour?

Cheers

Dennis

[multiweb]

Thanks Dennis. Not sure. I processed in CCD stack and I guess I was more focused in toning the sky glow down and getting rid of the noise. By the time I converted to color there was little left. RGB curves were a little offset too. Bad processing on my part. I might have stretched the data a little too far. That's why I want to give it another go under darker skies.

[AlexN]

nice.. next time try lowering the ISO and going a bit longer exposure... ISO3200 on any camera is going to introduce noise....

[multiweb]

Thanks Alex. I realise that but the camera won't capture much at ISO400/800. I used to do 2 min to 4 min exposures at ISO400/800 then stack them. First exposure was generally ok (bit of amp glow though) . Then noise considerably built up over time after multiple exposures.

This time I thought pushing the ISO to the MAX and cutting down dramatically exposure time won't let the camera "get so hot". The other advantage is that I don't guide for that long either.

Any other Pentax users out-there? How do you guys do it? :shrug: