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:
Are primes brighter and sharper than wide open zooms
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September 29th 05, 12:05 PM
Jan Böhme
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skrev:
On Wed, 28 Sep 2005 22:29:43 -0700, "Brion K. Lienhart"
wrote:
F:2.8 is solely based on the size of the lens. Obsidian is glass,
you can grind it into a lens shape, but if you use it as an element in a
lens, you're going to get some reallllllly slow shutter speeds. Of
course that's an extreme case, the difference between plain old glass
glass, and exotic flouro-silicates is only a few fractions of a percent.
So what was your point in bringing up a special case ulikely
to be implemented?
To illustrate the difference in principle between f-stop and t-stop in
an obviuos way, perhaps?
Jan B=F6hme
Jan Böhme