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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Recent content by LPT

  1. L

    Lee Thickett (Troubador) - R.I.P.

    I’m very sorry to hear this news. Rest in peace, Lee. Your posts and moderating were well done and reasonable and much appreciated.
  2. L

    Old E. Leitz Wetzlar 8x60 Binoculars

    According to the serial number it was made circa 1935.
  3. L

    Get well card for Lee (Troubador)

    Get well, Lee. Your posts are always enjoyed and appreciated and hoping to see you back soon. Frank
  4. L

    Kershaw undated binoculars

    These WWII period British No. 2 Mk II’s remained in service for many years after the war probably until at least 1979 when the Avimo 7x42 was introduced and were serviced and reconditioned many times during that period. On your example the original cover plates have either been replaced or the...
  5. L

    Ross Stepruva Question

    Regarding Ross history and serial numbering see the following files created by Terence Wayland: https://web.archive.org/web/20191104234153/http://home.europa.com/~telscope/Ross/Ross.serial.numbers.by.T.Wayland.xls...
  6. L

    Finnish Army binoculars

    Looks like a German 1930’s -WW2 Dienstglas 6x30 (standard infantry binocular) made by at least a dozen different makers including Zeiss, Leitz, Busch, Voigtlander, Swarovski, Hensoldt etc. The binocular was a close copy of the Zeiss commercial model Silvamar 6x30 introduced about 1910. The...
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    Inside a vintage German "Hanseat" 8x30

    Those prism wedges are just like the ones in the 3 or 4 Hartmann Berninas I’ve had. My guess is that you are correct and the bino was made by Hartmann. Prism wedges like that, though, are not new. Goerz used them on some binoculars before WWI and the Belgian OIP’s had them during the 1950’s...
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    Hungarian military binoculars 6*30

    It almost surely was made by Magyar Optikai Müvek (Hungarian Optical Works) usually known as MOM which had a long history and made among other things respectable quality military optics as well as civilian model cameras: Once a world-famous factory in Budapest, now a hardly known company - The...
  9. L

    How many types of Porro prisms?

    As far as I know Zeiss, Ross and Barr & Stroud were the only manufacturers ever to cement a field lens to a Porro II prism in order to reduce the number of air/glass surfaces thereby increasing light transmission and reducing stray light. The Zeiss examples were mostly 7x50’s and marked H for...
  10. L

    How many types of Porro prisms?

    The real difference in Porro I and Porro II prism systems is the geometries of their light paths and not whether the prisms are cemented or not. Most but not all Porro II arrangements have cemented prisms but there are some examples of air spaced Porro II arrangements, and most but not all Porro...
  11. L

    Which binoculars fall over?

    Many of the early non-stereoscopic models with closely spaced objectives (Zeiss’ patent did not expire until 1908 and some companies continued to make them well after that) are not very stable when placed upright. This is why Huet and some of the other early French makers put little knobs...
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    When Were Dielectric Coatings for Roof Prism Binoculars Introduced?

    I didn’t know that that phase correction coating (“P“ coating) introduced by West German Zeiss in 1988 was a dielectric one. This is interesting, and I have learned something. So, yes it is clear that the first dielectric coating used in roof prism binoculars was the Zeiss P coating to correct...
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    When Were Dielectric Coatings for Roof Prism Binoculars Introduced?

    You are referencing anti-reflective coatings which are different than dielectric coatings. Anti-reflective coatings are to reduce light reflection and increase light transmission through air-glass optical surfaces. Dielectric coatings are to increase total internal reflection in prisms where...
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    When Were Dielectric Coatings for Roof Prism Binoculars Introduced?

    Does anybody know when the first dielectric coatings for roof prism binoculars were introduced and which manufacturer introduced them? I believe this has been discussed on this forum before but cannot find the link. I would think John A. would know.
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    Help Identifying Galilean Binoculars!

    I believe it’s American made circa 1920’s - ‘30’s. I think by a company in Chicago.
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