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values

  1. Doug Kerr

    On standard aperture values

    Standard f-number values and their "labeling" is covered by standard ISO 517. I have only the first several pages (a "free sample"). In that is this list of "standard series of f-number marking": 05.-0.7-1-1.4-2-2.8-4-5.6-8-11-15-22-32-45-64-90-128 These are of course 1n 1-stop steps. There...
  2. Doug Kerr

    I was completely wrong!

    In several threads here over the past couple of weeks, I have been fairly emphatic that there could be sequences of numbers that would obey both of these "rules" for a substantial number of values: • If we go from one value to one 3 values further in the list, the value would change by exactly...
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