3. 21 Megapixel Full Frame Sensor

Though most medium and large format DSLRs have image sensors with more pixels, Canon’s 21.10 megapixel sensor is the largest ever in a 35mm camera. That these pixels have been distributed over a 36 x 24mm 35mm full frame sensor makes the camera especially suitable for professional photographers who need to extract every pixel of sharpness from full or cropped images.

"Full frame" means that any Canon EF (not EF-S) lens will work on the 1Ds Mark III without a major portion of the image it produces being cut off as it would be if the lens was used on a DSLR with a smaller sensor. It’s just like using a standard film camera to produce a 35mm slide or negative.

The new sensor was developed and is manufactured by Canon. The 1Ds Mark III’s 21.1 megapixels are arrayed in a 5632 x 3750 matrix and set at a pitch of 6.4 microns.

And to assure buyers it will continue making full frame 35mm lenses, Canon announced its new 14mm f2.8 II USM 35mm lens.