dhroberts wrote:
The choice of lens is relatively unimportant as long as you can fill the frame, with a slight preference for a short telephoto focal length such as 70mm to prevent the lens from casting shadows on the target. Much more critical is the lighting, which is best done with two lights, one on either side, at about 45 degree angles to the camera position. Placing a piece of glass over the object will help keep it all in focus; there will no reflections with the lights oriented as specified.