Looking forward to seeing your Mercury photo, good luck! I've been spending the last few days visually observing Mercury near meridian transit with my 6" f/8 Newtonian at 200X trying to spot Schiaparelli's 'Figure 5.' (Today is clouded out.) With just fair seeing, I've only seen the bright Apollonia region, with brief glimpses of bright Pentas, and dark Solitudo Criophori -- hey, I'll take what I can get! Mercury's CM (central meridian) is currently within a few degrees of when I took my photo on April 2, 2010, so you might be able to snag the 'Figure 5.' Schiaparelli was certainly eagle-eyed -- seeing features on Mercury through a small scope is no easy task, but it is an interesting challenge!
I suggest you compare your finished photo with a simulation of Mercury as seen from Earth that can be obtained from Nasa's Solar System Simulator ( http://space.jpl.nasa.gov ) at the same time and scale of your photo as a check onyour results. Looking at the simulation on a larger- size scale, you can see Mercury has huge numbers of varying-size craters. On your much smaller- size photo, adjacent craters will, for the most part, be only partially or not-at-all resolved -- along with crater rays, these blend together to appear as a single unit. A few of the larger craters will be clearly resolved, true physical features, not just light/dark albedo features.
Dave, thanks for the link to my 'Figure 5' photo. (Forum readers may also wish to see my other Mercury photo in the 'Gallery/Planets' section.)
Curt, my first telescope was a Criterion 1" AstroScope Refractor, a 14th birthday present!