Bob W wrote: > Conversely I'd expect to be able to put more pixels on a larger area, > but there seems to be some limiting factor that prevents the > widespread use of 24x36 (or perhaps it's just a Machiavellian > marketing trick to make people buy new lenses).
The limit is that the pixel sites on the sensor have a definite depth to them, rather like millions of bogroll tubes bundled together. Little lenses at the top, photoreceptors at the bottom. This means that light rays need to strike the sensor as near to perpendicular as possible, otherwise they just hit the sides of the tube, not the photoreceptors. Larger sensors have pixel sites further away from the central axis of the lens and rays are more likely to hit the sensor at angles further away from perpendicular than optimal, resulting in less light accessing the photoreceptors at the bottom. This is more likely with wideangle lenses. It's a problem that none of the manufactureres seems to have entirely overcome. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
