Pulled from another forum
Dang, I wish it did. I'd have done much better in those graduate level B&W courses at OSU. (All those are gone now, sad.) Unfortunately it's the two extremes of the grey scale that suffer, and have to be corrected, without the lose of the middle greys.
When checking a photo, it was always the highlights and shadows that I checked first. If I thought I could bring out more detail, then it was probably originally over saturated or under saturated and required correction. (Or bad contrast, and both ends of scale or middle are gone.) Once corrected, the middle greys might shift or vanish.
Bad contrast or exposure in an original are almost never recoverable. I would go the art route, and apply techniques to create something impressionable. Commercial art, in other words, not photography at that point. I would only do that if I thought I was losing an original exposure that I wanted really bad.
