X hits on this document

Word document

Archives of an email list on the history of binoculars. - page 40 / 150





40 / 150

leaving it for drip drying.

  I live in Denmark, our water has an extremely high level of calsium. And the book is danish, so this may be a local practice found by experience.  It also cloggs faucets, washing mashines, coffee machines and all that.  Maybe the process fills the alu oxide surface with calsium.

  In fact, if the inner surfaces of an alu Binocular is left uncoated, the risk of corrosion will be big, as the enclosed space will assemble moisture. Any contamination of the basic alu material will increase this behaviour. So if the alu bodies has traces of say, iron on the surface, this will increase the problem.

  This is probably the reason for the development of the electron alu alloy material. To make a less corrosive basic material.

  Another option is to use air drying in some way. Zeiss has made some military WW2 7x50 binoculars with silica gel inserts.  (silica gel is that stuff in the small white bags you see, when you buy electronic gear, like computers.)   So maybe the air drying not only was done to deal with visible moisture, but also to expand the working life of a binocular?

Michael Simonsen  mikedenmark@___ele.dk


Subject: Russian 6x24 etc

From: "G.H.Samuel" <G.H.Samuel@___c.uk>

  I bought one of these Russian 6x24 binoculars some years ago (very cheaply) and agree with Fan Tao's assessment. It is an excellent little binocular. In the UK it was distributed during the 1970's under the Helios brand name, but it had disappeared from the brochures by the end of the decade and I presume that it did not sell well. No doubt the best seller was the 8x30 which is still in production, together with a monocular version. I assume that the model went out of production. I have a range of versions of the 8x30, not all from the same factory if the logo is anything to go by. The 8x30 is a civilian version of a military model and all have excellent optical quality, although in some the image is on the green side. Most of the civilian versions are centre-focus, but an EF model - basically identical to the military ones but without the graticule - was available in the 1960s. I have to say that none of the old Helios brochures mention the EF 8x30, but it is shown in a 1960's Charles Frank catalogue. The monocular versions of the 8x30 are also of reasonable optical quality. I have models from 1971, 1981 (military with graticule), 1992 and 1997 and think that the optical quality is very consistent over the years. Given the price of these Russian optics, we are talking excellent value even if they do not match Zeiss.      Geoffrey Samuel


Subject: Russian 6x24

From: "Grimsey" <grimsey@___ld.com>

  I agree this is a very interesting little binocular.  I used to own one about 15 years ago and should not have sold it as it has taken almost that long to find another. They were certainly imported into the UK as I purchased mine new.They clearly do not come up very often and are very good value when they do. My own view is that the compact dimensions and wide field outweigh the yellowish image.    regards    Phil Grimsey


Subject: Russian 6x24

From: "tpress" <tpress@___v1.net>

  Fan Tao's description of the KOMZ 6 x 24 wide field binocular in the current List was extremely interesting and raises for me the question why a civilian glass such as this one would purposefully employ yellow images.

   While my survey is hardly exhaustive, virtually all of the Russian binoculars I have examined and many of the Soviet era East Bloc glasses all share the yellow image phenomenon. Do any of the List readers know the reason?    Regards,      Tom

Document info
Document views534
Page views534
Page last viewedWed Jan 18 22:36:15 UTC 2017