I can't really see what you are pointing to with the arrow (or is that just part of the scope and we should ignore it?) What you have is not MD I think...it is a plating disturbance that is frequently encountered on 1989-1992 cents.
Your microscope is really not designed for taking photos. Ideally, you would want an overhead light source above the specimen plate. The body of the microscope tends to block out light. Also, a variable zoom is much better than fixed focal lengths. With yours, there is no "in-between" for the best image. The new digital scopes on the market today have been perfected to do a pretty good job and do not cost that much. The only thing I definitely don't like about them is that they use built-in LED's for lighting and you can't control the intensity. For me, I'll stick to my traditional stereomicroscope which has zoom control and halogen lighting. Chris