Some details for general interest:
After WWII, there were two Zeiss companies in operation:
- one at the original location of Jena, in what was then the new nation of East Germany (it continued to use the original ‘Carl Zeiss Jena’ marking), and
- a seperate company at Oberkochen in West Germany (see a recent thread with information about the markings used at:
https://www.birdforum.net/showthread.php?p=3928021#post3928021 ) *
The East German company recommenced production using the pre-WWII designs
However, when the West German company commenced binocular production in 1954, it used all new more compact designs
The new West German models were notable for the use of tele-objectives i.e. where the 2 objective lenses are not glued together but spaced significantly apart
This meant that for a given focal length there was a shorter physical length, which allowed a binocular to be shorter than usual
(tele-objectives were also later used by Carl Zeiss Jena on some models)
The West German models also included gasket seals at various places to improve water tightness (they’re indicated in red on the first cross-section image)
* the two Zeiss companies finally reunited on 1991, following the reunification of Germany in 1990
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There were three versions of the West German 8x30 Centre Focus Porros:
A) 1954 to 1971
8x30 W, with 8.5 deg Field of View (150 m), and 9 mm Eye Relief
B) 1958 to 1968
8x30 B (v1), with 6.5 deg FOV (110 m), and 19 mm ER
C) 1969 to 1978
8x30 B (v2), with 7.5 deg FOV (130 m), and 19 mm ER
The first version had the very short eye relief typical to many binoculars of the era (other ‘pre-B’ era binoculars went to maybe 12 mm - as with most of the Swarovski Porros)
The second version - which was a significant advance at the time - introduced long eye relief eyepieces to binoculars, suitable for use by spectacle wearers
The B designation stood for brillenträgerokular, which translates into English as ’eyeglass wearers’
And the 19 mm eye relief would be considered acceptable even by current standards. However, it was accompanied by a significant loss of FOV
The third version somewhat addressed the loss of FOV while maintaining the generous eye relief
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In terms of optical construction:
- both the original and intermediate versions had tele-objectives. In contrast the last version had a conventional cemented doublet
- all three had different eyepiece lenses (both lenses and groups with the original and intermediate versions, and different lens shapes and thicknesses with the two B versions)
See the attached cross-sections for the three versions:
- the original is from a 1960 catalogue, from Mark at Miniature Binoculars at:
http://www.miniaturebinoculars.com/part3/Page1013.htm
- the two B versions are from Arek at Allbinos at:
https://www.allbinos.com/171.1-article-Legendary_binoculars_-_Carl_Zeiss_8x30.html
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In terms of easy visual identification:
- the original model had small diameter traditionally styled hard eyecups
- the intermediate model had longer eyepiece housings with larger soft rubber eyecups
- the last model had longer objective tubes than the previous two, along with slightly shorter eyepiece housings than the intermediate version
See the attached image from Renze de Vries which clearly compares the two B versions, from post #15 at:
https://www.birdforum.net/showthread.php?t=246368
John