John Francis wrote: >This means that an image overexposed by one stop would have counts that (after scaling) would range from 0 to 511. This is clipped to the range 0 to 255, with everything above 255 ending up mapped to 255. The visual effect is that the bright areas of the image are all washed out to white. An underexposed image, on the other hand, simply has values in the range 0 to 127. You can get back to the 0 to 255 range by simply multiplying all the values by two, although you lose one bit of precision.
Egad, that almost makes sense and math is not my strong suit (also still resting my brain from informational overload). And it's easier to lighten (successfully) in photo editing programs than it is to darken (successfully). Darkening tends to gray things out. Marnie aka Doe Well, in my experience. And that a nontechnical answer as well. :-)
