Lens Equivalent Calculator

How much a lens “zooms” depends on the size of the sensor or film. A “normal lens”, meaning a lens that is right between a wide angle and a tele lens has a focal length the same size as the diagonal length of the sensor. For a normal 35mm fullframe  this meens 43mm. Often rounded up to 50mm. It meens that the focalplane of the lens is 50mm away from the sensor. On a 4×5 large format camera the normal lens is 180mm. And a 90mm is a wideangle.

Use this tool to calculate how a lense on different sensor or film size compares to 35mm format.