Traduction de Christian Surle.

1954 : Leica breaks out with its new M3 body, which is going to become the referential rangefinder camera, and whose design will remain unchanged even after the numeric revolution of M8 in 2006, some fifty years later.
All these Leica M3 master key points can be found in this model, but using and ergonomics are improved by major modifications.

• Collimated telemetric viewfinder case, whose 0.91 ratio almost gives a very bright and real size picture. The telemeter base was doubled for increased accuracy.
• Film transport lever including a central released knob. The early models, until 1958, will require twin-shot operation. This was made intentionally to avoid film breaking in case of strong one-shot winding. The twin-shot reduction then allowed to slow down film advance.     
• No more 39mm screw mount, replaced by a specific fast bayonet allowing easy lens changing.
• New exposure counter with automatic zero setting, beside the transport lever.
• Bottom loading like on III models, but when removing the shoe you can free a device in the body back in order to ensure good film insertion (together with the film guide). Notice that the early film guides were black glass made... This device also allows inspection of the camera with no film inside.
• Speed selection is made by a unique knob, even for slow speeds. The early models feature : B – 1 – 2 – 5 – 10 – 25 – 50 – 100 – 250 – 500 – 1000 speeds.
• This scale was modified in 1957 as follows :  B – 1 – 2 – 4 – 8 – 15 – 30 - 60 – 125 – 250 – 500 – 1000. Models shown here feature both examples.
• Early models don’t feature field selecting lever under the viewfinder that allows to change focusing according to various lenses.

 Other minor modifications will occur along the 12 years and 226000 models of production... Rewind crank shape, number of visible screws, strap eyelets, etc...

This 1955 model, which has no field selection lever, is fitted with a f: 1.5/50mm screw mount Summarit with an M adaptor ring. This is a 1953 lens.

• The second 1957 body features the new speed scale. It is fitted with a 1956 f: 2/50mm Summicron directly fitted with the M ring.

Of course, many accessories are available, as the Leicameter, a cell that you can install on the flash accessory shoe. Notice that using this accessory could easily scratch the body cover.
This camera has also been used to ultimate wear by professionals. Its reliability and novelty made him the referential rangefinder.
Thus, it is very difficult to find a really brand-new one. The one who will have this chance can use a mythic camera like 50 years ago...

M3 model features a bright frames viewfinder with parallax correction. The frame automatically fits to 50, 90 and 135mm lenses. You need a finder correction for 35mm lens.
These are bayonet mount lenses.
Speeds go from 1 sec to 1000, + B.
You can add an exposure meter coupled with the speed-setting barrel.
 The viewcounter automatically gets back to zero when reloading the film.