Digital microscope photography (also called "microphotography") allows the photographer to take pictures of objects that are typically far too small to capture with normal camera lenses. By using a mounting piece, photographers can attach their cameras to microscopes and create images that would otherwise only be visible when looking through the microscope's eyepiece. Attaching a digital SLR (single lens reflex) camera to a microscope is especially easy, as SLRs feature interchangeable lenses. You need only remove your current lens and attach the camera to the microscope with a compatible adapter to start exploring microphotography.
Remove the current lens from your SLR by pressing the lens release button on the front of the camera and twisting the lens off. Angle your camera downward as you remove the lens to prevent dust from getting sucked into the body and adhering to the digital sensor.
Attach a T-mount adapter to your SLR camera body. Different SLRs have different-sized threads, so you must purchase a T-mount that matches the threading of your camera body. This threading will be referenced in your camera's manual and will be the same threads that are used to attach filters or other types of extension tubes. The number will probably be one of the following: 28mm, 37mm or 52mm.
Attach the T-mount and camera to the eyepiece of your microscope. The microscope will act like a normal lens attached to your camera.
Focus using the microscope's focus controls. Your SLR's autofocus will not work with the microscope as the T-adapter has no way to relay autofocus controls to the microscope.