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Interview with Olympus engineers and thoughts on 4/3

Olympus are running an extended interview with the engineers who worked on the Four Thirds system and the E-1 and E-300 cameras. It gives an uncommon insight into the design tradeoffs.

Most DSLRs available in 2004 are based on 35mm SLR cameras, which allows some reuse both by manufacturers and users. However, producing a sensor the size of a full 35mm frame is quite expensive, so cameras tend to have a "crop factor": only the center of the image plane is actually used to capture images.

Olympus have chosen to go with a new all-digital system based on a sensor somewhat smaller than that used in mid-level DSLRS from other manufacturers.

Manufacturers are fairly free to change sensors at will between fixed-lens camera models. However, for DSLRs customers expect to be able to reuse lenses between different generations of cameras. So by picking a particular sensor size and designing lenses to match, Olympus are committing to this size for perhaps ten years, which is an eon in electronics. Engineering tradeoffs can be tough, but particularly so when you're going to be stuck with them through four or more generations of technology.

Lenses specifically and bodies designed from size can be smaller than those based on the 35mm format, and therefore faster, lighter and cheaper at a given quality level. (Or the optical quality can be improved at a given price point, etc.)

On the other hand, a smaller sensor means that at a given resolution level, each sensor site must be smaller, and therefore possibly able to gather less pixels, and so less sensitive. At a given level of sensor technology, aperture and speed, larger sensors ought to have lower noise.

Or does it? Much of the light coming through a 35mm SLR lens falls outside an APS-sized sensor, and so is essentially wasted. The Olympus cameras should get more useful data bits per photon entering the lens.

To cut a long ramble short, the Olympus engineers seem confident that they will continue to be able to improve within 4/3 system, achieving quality comparable to medium-format and then large-format silver-halide cameras. Worth a read.

posted Mon 18 Oct 2004 in /photo/tech | link

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