With apologies to 19th century English poet John Masefield, I have an issue with my digital camera and none of the major camera vendors are helping me out. As we all learned way back in the days of Kodak Tri-X and silver-halide, the field of view of your basic human being is about equivalent to a lens with a 50-millimeter focal length projecting onto a 35-millimeter wide piece of film. Any shorter length lens creates a wider than human field of view while longer lengths zoom in for close-ups. So the basic, everyday lens that you had on your trusty old single lens reflex camera, in my case a Canon AT-1 which I had for about 27 years, was 50 mm.
Ah, but here’s the rub. Most affordable, or “prosumer,” digital SLR cameras have a sensor that’s smaller than 35 mm. In the case of my Canon Rebel XT, for example, it’s 22.2 mm by 14.8 mm, or about a ratio of 1.6 to 1 versus the size of old 35 mm film (it’s sometimes listed as “APS-C” in reference to a long-dead smaller size of old-fashioned film). That makes a 50 mm “regular” lens more like an 80 mm zoom lens. Fine, if I need a spiffier lens I can just buy a 31 mm lens which would be the equivalent of a 50 mm lens in the old days, no? Actually, no.
You see, only the cheaper digital SLRs like my $700-ish Rebel XT have these smaller sensor dimensions. More expensive models like the Canon 1d Mark III or Nikon’s D3, which cost $5,000 and up, have sensors that match the collection size of an old-fashioned 35 mm film camera. These are known as “full frame” cameras. And since professionals who use full frame cameras spend the most on lenses, the best lenses aren’t made in weird dimensions for we the cheapskate masses.
For example, if you want a lens that opens wider to take better pictures in low-light situations, what’s known in the biz as a fast lens, you have to buy a 50 mm one. I did just that last year, buying a fantastic Canon EF 50mm 1.4 lens that takes amazingly detailed shots in the shade. But I’m stuck with using it as a zoom because of the smaller sensor in my Rebel XT. What I need is a digital SLR with a full frame sized sensor that doesn’t cost an arm and a leg. Anybody listening? Anybody?
p.s. It is rumored that Canon may add such a camera to their line by updating a 2005 model known as the 5d. Hopefully it will sell for an affordable price.
Update 7/2/08: Close but no cigar: Nikon today announced a full-frame camera, the DX700, but it starts at $3,000 without a lens. I’m looking for something quite a bit less.
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