For a fixed picture resolution, it is much easier to design a large-format lens than a small one.
TTFN, Mark dan.grimes@xxxxxxxx wrote:
Mark Schubin: "Are you saying it's easier to make a lens that can provide 100 lp/mm lens than one that can provide 38 lp/mm? You'll have to do a lot of explaining to convince me of that."By no means! I'm saying that it is more expensive to make a lens to cover a larger format area and have 100 lp/mm than to make a lens that covers a small format area and have 100 lp/mm. When I first entered the discussion, I did not know that the discussion of resolving power was in relation to a fixed imager matrix.If we consider other qualities of the lens, such as contrast, MTF, even distribution, various distortions, etc., is it not more complicated to design the same qualities into a large format lens compared to a small one? Perhaps I am wrong on this. I gathered my knowledge while working with film where I spent a lot more money trying to cover 70mm film stock than to cover 35mm film stock. In the imaging department I was in, reduced resolution for a larger image area was not acceptable. And I worked mainly with fixed focal lengths rather than zooms.Educate me on video lenses. When I compare a lenses to cover the 2/3" video imagers to ones that cover 1/2" imagers while claiming the same relative qualities, the 2/3" lens costs a whole lot more. Perhaps they really don't have the same qualities?Dan Grimes
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