Leica M4 with 50mm f/2 and proxiphotography glasses
|Type||35 mm camera|
|Lens mount||Leica M mount|
|Flash||standard accessory shoe with separate bulb and electronic flash connectors|
|Dimensions||138 x 77 x 33.5 mm|
Leica M4 
The M4, introduced in 1967, is the direct successor of the M3 and M2, featuring framelines for 35mm, 50mm, 90mm and 135mm lenses in a 0.72 magnification viewfinder. It has the frame counter of the M3, with automatic reset after reloading.
Three ergonomic modifications were introduced in the M4:
- a different, angled film advance lever, as well as slightly different rewind, self-timer and frame selection levers
- a crank for rewinding the film, that replaced the telescopic knob of the M3
- a faster loading system that does not need a removable spool
loading system of a Leica MDa
Production of the M4 ceased in 1975.
Leica MDa 
A scientific version without a viewfinder was made as Leica MDa.
Leica M4-2, Leica M4-P 
Production of the M4 was wound down in 1972, in favour of the Leica M5, which had been introduced in 1971. However, the relatively bulky and expensive M5 met with a cool reception, and sales did not live up to Leica's expectations. Production of the M4 was therefore restarted in 1975, for Leica's 50th Anniversary, and in 1977 the company launched the updated M4-2, which was based on the M4's body, but with a streamlined production process that reduced manufacturing cost. The M4-2 added a hot shoe and motor drive compatibility as standard, but removed the self-timer.
The M4-2 was followed in 1981 by the M4-P, which added framelines for 28mm and 75mm lenses. The range continue with the Leica M6 in 1984, which was essentially an M4-P with TTL light metering. The M6 finally ceased production in 1998, although Leica released a special edition with a high-magnification finder in 1998.
Media related to Leica M4 at Wikimedia Commons