M3 .
Taken using an F/4.8 ten inch reflector, a Vixen Atlux mount, PHD auto guiding, an Atik 383L mono CCD camera and a set of Astronomik RGB filters.
I captured 60 second sub frames with matching dark frames combined with flat field frames to reduce noise and vignetting for the final result.
The total exposure time was 12 minutes for each filter.
