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jjjnettie
05-10-2007, 11:08 AM
I was shooting between the clouds and buffeted by the wind last night.
37 x 8 second exposures at ISO 800, F3.5.
Stacked in DSS, I used PaintShopPro and a little bit of Photoshop to bring out the detail. Neatimage to smooth out some of the noise.
No tracking, just the camera on a fixed tripod.
I wonder what it would look like if there were 100 images stacked? If the clouds ever clear, I'll give it a go.

h0ughy
05-10-2007, 11:12 AM
well done JJJ - all you need now is the observatory to be up and you can do this from inside protected from the wind

jjjnettie
05-10-2007, 11:21 AM
Hmm yes. The tax cheque is in. Won't be long now.

janoskiss
05-10-2007, 11:31 AM
100 images would probably not look all that different from 37. At best you would reduce noise by about 40%. But I suspect you are really pushing the camera to its limits there (working not much above the so-called noise floor of the CCD) so actual improvement would be considerably less than that.

Dr Nick
05-10-2007, 03:38 PM
A little grainy, i think if you stacked more of them it would be great! ;)

acropolite
05-10-2007, 07:43 PM
Nice shot jjj, I think you'll find that you could probably multiply the exposure time by at least 3 times (24 seconds), that will allow you to drop the ISO and lessen the noise. I have taken widefields (at the zenith) at 30 seconds with an 18mm F/L on the 20D with no appreciable star trailing.