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EXIF Focal Length Issues

One of the major differences between digital and 35mm photography is the sensor size. The digital sensor is usually smaller than 35mm film, capturing a smaller portion of the image passing through the lens. Essentially cropping the image. This cropping is also known as the 'Focal Length Multiplier.' This multiplier changes the behaviour of lenses used for both digital and film use. The multiplier is used to clarify the issue; a 50mm lens used on a camera with a 1.6 multiplier will produce the results of a 80mm lens.

For most long lens users this multiplier is more of a blessing than a curse. After all who doesn't want their 300mm lens turned into a 480mm lens. But for the wide angle users their 20mm lens just turned into a 32mm lens. So to get the same wide angle results special 'digital' versions of wide angle lens are available from 10 to 22mm in length.

So to give the viewer a frame of reference, regardless of the camera/lens combinations I've used, I've 'normalized' the focal length data by converting all focal lengths to their 35mm equivalent.