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Photography Question 

135 Format

I just need to know why a 35mm format is also called a 135 format. Where does the number 135 derive from? Same with the 120 format - where does one get the number from. For a 4x5 and a 8x10 it is pretty clear.

Anyone with the answer would be much appreciated if you could share it with fellow photographers. Thank you very much.

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1/11/2001 9:47:04 PM

John A. Lind
BetterPhoto Member Since: 9/27/2001
  Hi "kennyweb." An interesting history question! The numbering scheme was created by Kodak during the early 1900's before W.W.I when Kodak began marketing large roll films to replace using glass plates in old view cameras. [Before about 1890, most "film" was emulsion on plates of glass!] Originally, the size or camera type was listed on the box. Very quickly, there were so many cameras and too many sizes of film, so Kodak started numbering them beginning with "101" and counting upward sequentially. "120" just happens to be where they were when it got numbered.

They didn't follow this scheme of sequential numbering rigidly. My guess is they used "135" for 35mm still camera film because the number had not yet been used for another size and simply put a "1" in front of the "35" to aid in recognition of the size and fit it into their three digit scheme. 35mm still camera film has its very direct roots in 35mm cinema film created by Thomas Edison, right down to the size and spacing of the sprocket holes. When the first successful 35mm still camera, the Leica A, was released in 1926, it used readily available 35mm cinema film. You had to get a reel of cinema film and load your own cartridges in a darkroom. For the longest time, 35mm film was also called "Edison size" for this very reason.

Also, some numbering like 620 and 220 have roots in prior sizes, in this case "120" size. 620 (no longer made) is the same as 120, except it's wound onto a slightly smaller diameter spool to fit into a slimmer folding camera. 220 is the same as 120, except it's twice as long. To use the same size spool, the paper backing for 220 is only a leader at the beginning and end (on 120 it backs the entire roll). So, although they originally started numbering sequentially, Kodak has leaped around in its numbering for other reasons at times. I have yet to figure out why 828 (another discontinued film) was numbered 828. Recently, some number have been used over again, such as 110 (pocket instamatic). The older, larger instamatic was 126 size.

So there you have it . . . it all started with a sequential numbering scheme by Kodak to eliminate confusion about the different sizes. It has continued with deviations from the sequential system to occasionally using number that helps people remember what the size is and how it relates to a prior size it was derived from.

-- John

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1/24/2001 11:09:14 PM

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