As part of the FE line of lenses, the FE 50mm f/1.4 ZA is designed to cover the Sony a7- series cameras’ full-frame sensors. When used on a full-frame camera, the lens’ fast aperture, normal field of view and light weight make it useful in nearly any type of photography or video, and it’s dust/moisture resistant sealing allows you to use this lens in less than ideal conditions. This lens can still be used on cameras with an APS-C sensor, however it would be equivalent to using a 75mm lens. The f/1.4 aperture allows you to use the lens in low light situations, and gives you optimal depth-of-field control. The lens’ rounded eleven-blade aperture diaphragm gives images smooth out-of-focus areas when you desire a shallow depth of field. When manual focus is not ideal, the direct-drive super sonic wave motor autofocus system provides a very responsive, accurate, and nearly silent autofocus function. The manual aperture ring allows you to disengage click stops for smooth aperture adjustment when shooting video.