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The Leica M6 is a rangefinder camera manufactured by Leica from 1984 to 1998, followed by the M6 "TTL" manufactured from 1998 to 2002. In 2022, Leica introduced a new version of the M6, based on the technology of the Leica MP, but staying true to the design of the M6.
The M6 incorporates a light meter within the body dimensions established by the previous Leica M3 and Leica M4 models. The light meter was operated by depressing the shutter halfway, had no moving parts, and used LEDs to display readings in the viewfinder. Informally it is referred to as the M6 "Classic" to distinguish it from the "M6 TTL" models, and to indicate its "Classic" M3 dimensions.
The top and bottom plates were made from lighter, cheaper magnesium alloy rather than the heavier machined brass of the M3 and M4. The M6 and M6 TTL are mechanical cameras; all functions except the light meter work without batteries, unlike the succeeding M7, which needs electrical power to operate properly.
Leica M6 variants
M6J – 1994. A collector's edition of 1,640 cameras to celebrate the 40th anniversary of the Leica M System. Notable for its introduction of the 0.85 magnification finder, the first high-magnification finder since 1966, and the basis for the 0.85 cameras to follow starting in 1998.
M6 0.85 – 1998. The 0.85x magnification viewfinder was offered on regular production cameras for easier and more accurate focusing with long focal length or wide aperture lenses, such as the 50 mm f/1.0 Noctilux and 75 mm f/1.4 Summilux. The 28 mm framelines are dropped in this model. Only 3,130 of these cameras were made (all black chrome), so they are among the less common regular production of the M6.
M6 TTL – 1998–2002. The M6 TTL replaced the M6, which ceased manufacture. Originally available with 0.72x and 0.85x viewfinders, in 2000 a 0.58x viewfinder version was added to the line. The lower magnification viewfinder makes it easier to see the 28mm framelines, especially when wearing glasses. The shutter dial of the M6 TTL is reversed from previous models, turning in the same direction as the light meter arrows in the viewfinder; this feature has continued in the M7, M8, and M9, but not the MP, which returned to the older, smaller diameter, opposite direction shutter speed dial. One of the key differences to the M6 "Classic" is TTL flash capability with dedicated flash units, such as the SF-20. The added electronics increased the height of the top plate by 2 mm.
M6 reissue – 2022. In October 2022, Leica announced a variant of the MP with cosmetic changes to closely but not exactly replicate an early production M6 with 0.72x viewfinder magnification. It features brass top and bottom plates, "Leitz" red dot logo, "ERNST LEITZ WETZLAR GERMANY" top plate engraving, M11-type abrasion-resistant black lacquer and leatherette, and "MADE IN GERMANY" embossing on the back.