Since the camera will out-resolve a very sharp lens by almost a factor of 2
Wrong. Read below. People are not understanding the charts in the Castleman link. The right chart is MTF. The OP mentioned resolution. That is the left chart. The left chart is the system resolution of the Canon lens plus Technical Pan film. It is NOT the resolution of the Canon lens alone!
System resolution R can be approximated by:
1/R = 1/S =1/L where S is sensor and L is lens
If you put in 160 for sensor resolution, and 160 for lens resolution, the formula shows system resolution at exactly half, at 80 lp/mm. The system resolution is always lower than the weakest component.
I read elsewhere that Technical Pan film resolution is 160, using a certain developer. But the Castleman chart shows the system resolution at 88 lp/mm. Thus the Canon lens must be higher than 160. It is 195, as calculated by the formula.
This is a reasonable number for a prime lens at optimum aperture by a top manufacturer. Lens resolution is measured by examining a projected aerial image in a microscope.
Another point to make, is that print quality (and system quality) continues to improve, even if the body greatly out resolves the lens. Improvement does NOT slam to a halt, if the body out-resolves the lens.
Oct 31, 2008 at 01:36 PM
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