The FED 4 rangefinder camera was produced by the FED factory in Kharkov, Ukraine from 1964 to 1980. It has interchangeable lenses, fitted with a Leica-type M39 screw thread. The normal standard lens supplied was a 53mm f2.8 Industar 61. It has a focal-plane shutter, with speeds from 1s - 1/500s +B, with flash sync at 1/30s and a self-timer. The frame size is 24x36mm on 35mm film.
Unlike its predecessors (the FED 2 and FED 3), the camera has an uncoupled selenium meter, with the sensor on the front of the top housing, in front of the speed dial. The meter has its readout scale on the left of the top-plate, with a match-needle linked to a calculator dial. This placement of the meter calculator leaves no room for a rewind knob on the top; the rewind is a thumb-wheel mounted half-way up the top-housing, on the end of the camera. The top housing increases the size (especially the height) of the camera very significantly relative to the earlier FEDs.
The Fed 4 comes in two versions. The FED 4a (F190, made from 1964-1971) has knob wind, with a plain front to the top plate; a large gap between the viewfinder window and the top; a circular bezel around the rangefinder window; and the name engraved on the front, between and above the rangefinder and viewfinder windows. It has strap lugs. The FED 4b (F192, made from 1969-76) has lever wind, and rectangular borders to the rangefinder and viewfinder windows, matching the height of the meter window. The viewfinder is larger, and the name is printed on the plate around the rangefinder window. It has no strap lugs. Type b comes in 3 variants with slight cosmetic changes.
Foto-Quelle sold the FED 4 in Germany as the Revue 4 (F194). Special editions were produced for the 1980 Olympics in Moscow, and the 50th anniversary of the October Revolution in 1967.