Nikon FM2 viewfinder

The viewfinder of FM2 is designed with a fixed structure. The shutter speed value of the camera is optically refracted on a small digital transparent disk linked by a shutter speed adjusting disk gear and displayed on the left side of the viewfinder. The selected aperture value on the lens aperture ring is also displayed directly above the viewfinder through optical refraction (this is a classic design in Nikon manual series). This method is simple and clear without electricity, but it is difficult to observe when used in a dark environment. The pentaprism in the viewfinder of FM2 is coated with a special silver film to increase the light passing through the pentaprism.