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optics for Schmidt-Cassegrain telescope
optics for Schmidt-Cassegrain telescope

optics for Schmidt-Cassegrain telescope

Datecirca 1943
Inventory Number2007-1-0024
ClassificationTelescope Part
Subject
    Maker Polaroid Corporation 1937-present
    Cultural Region
      Place of Origin
        Dimensions15.5 × 9.8 × 9.8 cm (6 1/8 × 3 7/8 × 3 7/8 in.)
        Box: 17.5 × 10.5 × 10.5 cm (6 7/8 × 4 1/8 × 4 1/8 in.)
        Material
          DescriptionCylindrical in shape, the design of this 4-inch telescope is based on a spherical primary mirror and a Schmidt corrector plate to correct for spherical aberration. It is also called Cassegrain because it has a convex secondary mirror, a perforated primary mirror, and a final focal plane located behind the primary.

          The optics is very good, and protected by a piece of lucite at the end of the optical tube. This telescope was most likely used in conjunction with another instrument or camera.
          Signedon telescope: 1450 / Model C3 / Polaroid Corp., / Cambridge, Mass lower part of storing box, hand-written: SCHMIDT TELESCOPE / POLAROID / 1943 / L. HYDE
          Inscribedon a tag: from Byerly 10/13/64 on a tag: Replace Schmidt Jars out of focus. M. Rogers
          1-foot Cassegrain reflecting telescope
          James Short
          Date: circa 1758
          Accessories: dust cap; object glass micrometer (0059)
          Object number: 0053
          24-inch corrector plate for Jewett Schmidt photographic telescope
          Perkin-Elmer Company
          Date: 1942
          Accessories: crates
          Object number: 2023-1-0015a
          33-inch primary mirror for Jewett Schmidt photographic telescope
          Perkin-Elmer Company
          Date: 1942
          Accessories: crates
          Object number: 2023-1-0015b
          pair of apodized gratings for 23-33 inch Jewett Schmidt camera
          Dow Chemical Company
          Date: circa 1942
          Accessories: crate
          Object number: 2023-1-0017
          aluminum alloy apodized grating for the 24-33 inch Jewett Schmidt camera
          Dow Chemical Company
          Date: 1942
          Object number: 2023-1-0017a
          brass alloy apodized grating for the 24-33 inch Jewett Schmidt camera
          Harvard College Observatory
          Date: 1942
          Object number: 2023-1-0017b
          Gregorian reflecting telescope
          English
          Date: 1715-1720
          Accessories: solar filter; lens; awl; dust caps.
          Object number: 5002
          2-foot Gregorian reflecting telescope with split object glass micrometer
          James Short
          Date: circa 1763
          Accessories: split object glass micrometer; spare secondary mirror in tin box (0002b).
          Object number: 0002
          2.75-foot Gregorian reflecting telescope
          Jean-Baptiste-Charles Gonichon
          Date: 1733-1763
          Accessories: dust covers for tube and eyepiece
          Object number: DW0814
          2.5-foot Gregorian reflecting telescope
          Gaspard Rochette
          Date: circa 1785
          Accessories: dust cap for eyepiece and tube
          Object number: DW0164
          1-foot Gregorian reflecting telescope
          English
          Date: circa 1735
          Object number: 0054