Ricoh GXR Interchangeable Unit Body with Ricoh LENS A12 50mm F2.5 MACRO Camera Unit, 12 Megapixel Lens, image sensor, and image processing engine comprise an integrated unit which can be changed to match the scene being photographed. World's smallest and lightest digital camera with interchangeable lenses System potential expanded through use of interchangeable units Body exterior is die cast magnesium which has a strong track record in the GR series The automatic exposure modes include program shift mode, shutter priority mode, and aperture priority mode.