Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: Ian on Jun 29, 2002, 09:49:00

Title: another jewel in the sky
Post by: Ian on Jun 29, 2002, 09:49:00
M13 this time.

(http://212.104.156.50/oas/m13small.jpg)

[ This Message was edited by: Ian on 2002-06-29 01:50 ]
Title: another jewel in the sky
Post by: Ian on Jun 29, 2002, 10:16:00
pressed the wrong button :sad:

[ This Message was edited by: Ian on 2002-06-29 22:46 ]
Title: another jewel in the sky
Post by: Whitters on Jul 01, 2002, 06:38:00
Hey that's realy good. What were the exposure times, and did you get a better polar allignmant?
Title: another jewel in the sky
Post by: Ian on Jul 01, 2002, 19:06:00
much better but not perfect polar alignment (still got to get the polar scope aligned along the RA axis :roll: ) but the focus was much better.

This image was 17 of 20 ten second images with a five frame averaged dark. Then just a little histogram stretching. You can make out more stars in the original bitmap by stretching further but the pic isn't as pretty. I did want to have a crack at M27 too but my drive batteries died. I'm probably gonna have to do some more work on the mount too, there is a frightening amount of slop in the drives.
The other problem for larger DSOs is field size.  At f6 (prime focus) the ccd is 11x8 arcminutes in size. I'll have to sort out a focal reducer :sad: