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    Chromatic Aberration, CA, what, why, how?

    History of optics Wikipedia says lenses were developed by the ancient Egyptians and others. There are very old lenses in museums about 3,000 years old. Visby lenses have aspheric magnifiers from the 11th century. It is probable lens aberrations were known long ago. B.
  2. B

    Chromatic Aberration, CA, what, why, how?

    CA was very well known in the early 1600s, because telescope objectives were made of one piece of glass and had to be very long to be useful. Newton officially said only reflectors were CA free, although he actually knew otherwise. It was only when Dollond took to making doublets with crown...
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