[Leica] How did 50mm become the "normal" lens for 35mm cameras?

[Philippe]

Just remembered a conversation heard years ago between M enthusiasts here, they were debating on the actual FL of varied Leica 50mm - and got out impressive differences between luxes, crons, elmars, etc 
Anyone knows more about this?
Ph


Le 17 sept. 2016 à 19:46, Bryk Oliver <oliverbryk at comcast.net> a écrit :

> In 1953 I was a student in the US Army Signal Corps Photography School in Ft. Monmouth, NJ. After passing still photo school (4x5 Speed Graphic) I was selected for “Combat Cameraman” class (35mm b&w cinematography) using the Bell & Howell “Eyemo” handheld newsreel cameras well as Mitchell and Maurer studio cameras. 50mm was the normal lens for these 35mm cameras.
> 
> A booklet “Instructions for the use of the Leica Camera Models c, f & g” (referring to the Leica III series) published by Hove Books Ltd. states that “THE STANDARD LENS OF THE LEICA is the world famous ELMAR having a maximum aperture of f/3.5 and a focal length of 50mm”.
> 
> In the book “Leica M Advanced Photo School” by Günther Osterloh, 2nd English ed., published by Lark Books in 2005 (the original German edition was published in 2002) is a section “Normal focal lengths”:
> 
> "Lenses with focal lengths that correspond approximately to the diagonal of the negative format are called normal lenses. In the 35mm format of 24 x 36 mm the diagonal measures about 43 mm. For practical reasons and for reasons of better quality, however, more than 75 years ago Leitz decided to use a standard focal length that is nearly 10 mm longer. And that is still the case today; standard lenses for Leica cameras have a focal length of 52 mm. This holds true even when the engraving around the front element of the lens reads only 50 mm.”
> 
> “For the novice, taking pictures with this lens is easy because its angle of view of about 45 degrees most closely corresponds to the natural coverage of the human eye.” 
> 
> Respectfully submitted,
> 
> Oliver
> 
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