This is the inside of my grinder at 20x
and this is the inside of my grinder at 400x
DC, the microscope has a lens that moves very close to the subject matter and it isn't a digital zoom, however I only have the option of focusing on a 20x or 400x scale.. I would say you def have a great bit of kit and I might return this and get your one.
Cisco, i put the subject matter under the scope then adjust the zoom to focus at 20x and then wind the zoom right in to the focus point at 400x on these scopes you only have 2 focal lengths.