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exposure

  1. Doug Kerr

    Why the f-number matters in exposure

    One may wonder why the measure of the "taking aperture" we know as the f-number (the ratio of the focal length of the lens to the diameter of the aperture) is seen as one of the pivotal parameters of exposure. It might seem that the diameter of the aperture itself (or perhaps its area) would be...
  2. Doug Kerr

    The APEX system (Additive System for Photographic Exposure) - updated technical article

    The APEX system (the Additive System of Photographic Exposure), introduced in 1961 (good grief! I was only 25 years old then!) defines a system of specifying various factors involved in photographic exposure (exposure time, film sensitivity, etc.) in logarithmic form. Its main objective was to...
  3. Robert Watcher

    A little brick and mortar exposure again

    What to do with tens of thousands of photographic images. That almost stifles my incentive to go out each day and photograph. At this point in my life / career, I’m not concerned or even expecting to make money from my photography. But it sure is nice to have a venue where people can see my...
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