Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: JohnP on Dec 13, 2005, 21:32:35

Title: This is bad.... NGC891..
Post by: JohnP on Dec 13, 2005, 21:32:35
Hi All,

Wasn't sure whether or not to post this..... before you look it's bad... It's my first attempt with my newly modified 1004 security camera. It's a 'didi' little security webcam with a B&W ccd chip (same as Chris's old SAC8) that took me about a year to modify & get working (just don't ask me about it...) In fact if I hadn't spent so many hours on this project I would have given up months ago.  Anyway image is taken at prime on my MN56 & represent sum of 33 X 15 sec exposures (no peltier cooling) - darks & synthetic flats applied. Chris gave me a demo of AIP4WIN & I have just about played with every processing/ post processing technique/ algorithm. Don't ask me what I did I never documented it all but I think just about everything & a bit more - in fact I was in two minds as to whether or not publish it as it's almost too far processed. The image still has loads of problems - bloated stars, gradients on the background & dark shadows to the right of the stars - still the camera only cost £40. I'm very jealous of Mikes Ha images of this a few months back...

I've a long way to go but I guess I can use this as a starting point... Peltier cooling next I think...

Cheers,  John


(http://homepage.ntlworld.com/john.punnett/graphics/oas/ngc891_processed.jpg)
Title: This is bad.... NGC891..
Post by: Rocket Pooch on Dec 14, 2005, 18:45:21
Hi John,

You must do this http://www.leadbeaterhome.fsnet.co.uk/1004xcam3.htm

It shows the problems you are having, the lines may be readout noise, try the bias frames and also create a master flat as well.

Chris
Title: This is bad.... NGC891..
Post by: JohnP on Dec 15, 2005, 09:12:37
Cheers Chris - I've been studying Mr Leadbetter's pages in detail & also had a few emails with him. I'll probably adopt his method of cooling (even just for a quick test) & see what difference it makes.

Thks,  John