I have no idea what I'm doing with colour but here's a first go at Ha and OIII imaging.
(http://www.jumpers4goalposts.org.uk/images/Astronomy/Messier/M42-colour.jpg)
Which color channel did you add the OIII frame to?
Chris could you post both B&W images I would like to see what you recorded with the OIII filter.
Cheers
The images we're taken at different times so there not a matching pair and I really did not have a clue what to do on the colour. But here they are. I probably could have done with approx 40 sec exposures on the OIII not the 20sec I used.
OIII Taken 26/12 with quite a lot of cloud about 20x20sec
(http://www.jumpers4goalposts.org.uk/images/Astronomy/Messier/M42-OIII.jpg)
Ha Taken 18/12 excellent conditions
(http://www.jumpers4goalposts.org.uk/images/Astronomy/Messier/M42-HR-20041218.jpg)
[ This Message was edited by: csuddell on 2004-12-28 10:32 ]
Had another play.
(http://www.jumpers4goalposts.org.uk/images/Astronomy/Messier/M42-OIII-Ha-20041226.jpg)
Sorry paul forgot to say the OII was GB Ha R
Pretty cool Chris,
As you suggest, to start with the exposure times for RGB should be the same to get a rough approximatirion of color balance.