Hi Andrew
I think that's a really nice picture...Was there a focal reduce used? It's like a prime focus f/4.5 photo of about 20 minutes exposure taken with 1000 ASA film!
I had a go at M42 also the other evening with an 80mm refractor - first time for me actually but with a 1/2 CCD chip could barely fit it on the frame at f7.5.
see:
http://myastroshop.com.au/guides/swed80.asp
Steve