Ansi contrast measurement.

[mmene]

<p>I wonder if there is a way to measure ansi contrast of an image. That means the ratio of <a href="http://www.google.gr/search?hl=el&client=firefox-a&rls=org.mozilla:el:official&hs=Opq&ei=gVwKS9LCFYyusAbK54zOAQ&sa=X&oi=spell&resnum=0&ct=result&cd=1&ved=0CBcQBSgA&q=luminosity&spell=1" ><strong></strong> </a> luminocity between the brightest and darkest area,without using a lightmeter.</p>

[Ed_Ingold]

<p>You can measure the luminosity of an <strong>image</strong> using one of several tools in Photoshop. You will get a range not exceeding 0 to 255. Luminosity range of the <strong>subject</strong> can only be determined with a light meter, because nothing that produces more than 255 or less than zero is registered in the image.</p>

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