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  1. H

    Real calcium fluorite in NL binoculars?

    Right Binastro. That binocular used Fluorite doublet objective lenses from the Takahashi FS-60 scope cobbled together with the prism housing and eyepieces from a 7x50 binocular. That's the only "small" binocular with genuine Fluorite I recall.
  2. H

    Real calcium fluorite in NL binoculars?

    Thanks for the confirmation, Robert. For small, low magnification binoculars I don't think there is much reason for anybody to use Fluorite or an equivalent glass type with an Abbe # of 95. Of course, that won't prevent the use of loose marketing terms that imply the use of Fluorite. Henry
  3. H

    Real calcium fluorite in NL binoculars?

    Hi Robert, I think I do see a barely visible wisp of a trail in the back element of the cemented doublet. You would expect a very dim trail through the "FL" glass and in this photo it's further obscured by the bright interior background. The front element has such a bright trail because it's a...
  4. H

    Real calcium fluorite in NL binoculars?

    I just checked with a green laser. The objective elements are all glass - no Fluorite. However, I have found that the corrections for both longitudinal and lateral chromatic aberrations are exceptionally good in the 8x42 NL, I believe the best I've seen in a binocular.
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