Monday, January 26, 2009
Digital Cameras: New Lens Numbers Needed
Posted by John Lane in "Digital Home Articles & Resources" @ 09:00 AM
"You know what's driving me crazy? This inevitable parenthetical: "The Nikon D60 comes with an 18-55 mm lens (27-82.5 film equivalent)." ... So when we talk about the "film equivalent" of lens focal lengths, who, exactly, is supposed to benefit from this information? The audience of people who have a clue what that means is shrinking daily. To make matters worse, there's no standard multiplier. A 24 mm lens on a Nikon digital camera does not give you the same wide angle as a 24 mm Canon lens. (You'd multiply the Nikon by 1.5 to get the "film equivalent," the Canon by 1.6.) ... But my point is that the "film equivalent" number is no longer a good measurement. Fewer and fewer people know or care what that means. ... It seems, then, that what we really need is a completely new measurement system that's consistent across all lenses, all cameras. Not even millimeters; something more useful, more recognizable."
The New York Times' David Pogue makes a good point that lens sizes don't give the casual photographer the information he or she needs. Most snapshot takers concentrate more on zoom factors than where the zoom begins and don't realize that some cameras like the 2.5X zoom Panasonic LX3 (24MM) starts at a wider angle then others like the 5X zoom Canon G10 (28MM). The obvious solution for non-DSLRs would be to switch over to field-of-view measurements and away from millimeters. However, for DSLR's, this doesn't work, since the same lens has different field of views on different cameras due to the crop factor. For that reason, I think we are stuck with the old terminology, kind of like QWERTY keyboards.