What is 35mm? What does 35mm mean?

If you've heard shop talk amongst photographers or read some photogrpahy books you may have come across the measurement "35mm" now and again. What is 35mm? What does 35mm refer to?

In the days before digital cameras when cameras had that old style roll of film inside on which photos were printed, the film had a certain width and the standard width of film since the early 1900s, was 35mm.

Movies and video were and still are printed on 35mm wide film too. The big screen IMAX films however are often on 70mm film.

In digital cameras today there is no film. Instead you have a microchip which picks up the light and translates it into electrical information, which is then transfered onto the camera's memory card in order to take a photo. The size of the microchip differs between cameras. The larger the microchip the better quality your pictures can be. And the larger the microchip, generally the more expensive the camera will be.

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If you want to read more about 35mm film you can visit wikipedia's entry on it.

Image by Jay Holben