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photo by Donald Kinney
Generally speaking, photographs are supposed to have a full range of tones; from dark and black to light and white, but on occasion atmospherics prevail. If you look carefully you might detect a very foggy Mt. Tamalpais.
The Histogram is a graphical representation of the brightness values in a photograph. Adjustments are made by sliding the small triangles at the base. Normally I would utilize the blank space on the right side of this Histogram--that would cheer-up the tonal range substantially, but the result wouldn't have been true to the subject.