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Re: [Rollei] Define "Contrast" and "Sharpness"
- Subject: Re: [Rollei] Define "Contrast" and "Sharpness"
- From: Jan Böttcher <jab
- Date: Fri, 15 Feb 2002 10:38:27 +0100
- References: <F3AkwtsQztQoPAzdaQY0001ddc6
yes, a tautology is something tautological!
Id rather say:
contrast means measuring how dark(-grey) black subjects/areas) will be reproduced
and how light(grey) white areas/subjects will be reproduced, (good contrast lense will
reproduce black as black, not dark-/medium-grey, and white as white not ligth-/medium
and sharpness/resolution refers to the finest pattern reproduceable disregarding the fact,
that black has turned into 49.5%reflection and white has turned into 50.5% reflection,
the finer the pattern got.
The rest in fact is best seen in examples as in Zeiss's propaganda pamphlets.
Dirk-Roger Schmitt wrote:
> very easy.
> You just need a graph of contrast vs spatial frequency or vs. spatial
> wavelength for each lens to discuss differences.
> That is the only way.
> At 23:49 14.02.2002 -0800, you wrote:
> >Okay all you optics nerds. Here yer chance to show some of us lesser
> >scientific underlings a thing or two. My question is this-
> > What exactly is contrast, and sharpness. Explain how they relate to
> > each other in the context of a discussion of a lens - (example - the
> > differenc ebetween a id 50's Tessar, and a F series Type 4 Planar) -