Histograms are the solution to a fundamental problem in photography: Our eyes don’t always tell the truth. Have you ever been in a dark room, turned on your phone, and felt it blind you like nobody’s business? The same thing can happen in photography. Several times, I’ve taken pictures at night, and they look great on my camera’s LCD — until I open them the next day on my computer and realize they’re all hopelessly underexposed. Enter the histogram. This is one of the best ways to know exactly, mathematically, the brightness of your pixels. So, let’s dive in.
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