Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site brl-sem.ARPA Path: utzoo!linus!philabs!cmcl2!seismo!brl-tgr!brl-sem!ron From: ron@brl-sem.ARPA (Ron Natalie) Newsgroups: net.rec.photo Subject: Re: Re: Product Quality: Color prints from slides (contrast buildup) Message-ID: <468@brl-sem.ARPA> Date: Thu, 31-Oct-85 15:54:14 EST Article-I.D.: brl-sem.468 Posted: Thu Oct 31 15:54:14 1985 Date-Received: Sun, 3-Nov-85 10:37:44 EST References: <298@tekig4.UUCP> <349@vaxwaller.UUCP> Distribution: net Organization: Ballistic Research Lab Lines: 13 > The contrast range of a medium basically is the difference between its > blackest black and its whitest white. Actual scenes can have an apparent > range of over 10 f-stops; the greatest range typically available on B&W > paper is about 7 stops. I disagree with this simplistic view. The black and white intensities are not what determines contrast, but the number of distinguishable intensities. Take it as sort of a visual S/N ratio. Both grade 1 paper and Kodalith have the exact same white and black values, but you can see more shades of grey on the lower contrast paper. I'm don't think f-stops are a valid unit here. Actual scenes is a misnomer here as well. What you are really saying is the human eye has a much greater contrast range than any film does.