He goes on describing how the optical axis of the monocular is aligned with the fixture for the axis between the two half parts of the binocular.
After the Binocular was fixed, each "barrel" or telescope was aligned individually, to the common axis.
This appear to have been a revelation for the danish army officer in charge.
And right now, I am thinking: How does one collimate an old Goerz Binocular, where there is no central axis to fix it with...only two singular hinges?
Either the fixture for this must be difficult to make, or maybe they didn´t collimate those field glasses correctly.
In fact, there migth be more to that large cup like knob at the far end of the axis on many military binoculars of the time.
It may be present because military binos must be able to be collimated.
And then it is part of the fixture for this process.
I have been wondering, why many of these cups did have such a nice smooth concave hemispheric surface. It looks nice, but it may have a function too.
Not as I thought, just a knob for fixing the IPD of an individual user.
Presently...does a missing axis, mean that the producer has no intention of making collimation possible.
In other words..is a central axis bar a mark of quality?.
Michael Simonsen Mikedenmark@___ele.dk
Some models of binoculars, including an early Goerz model, did not have a center post, but used two narrow hinges at the front and back of the binocular. The Goerz was quite solidly built and not inferior quality. Collimation would involve mounting the binoculars on the hinges, with a pair of holes where the axis should be. I'd guess a jig would do the job, but I'm sure it wasnt easy. --Peter
Subject: Part required for B & L 6 x 30
From: "Keith Shackleton" <hkshackleton@___t.com>
I have recently acquired a pair of Bausch & Lomb 6x30 porro prism binoculars. They are inscribed on the right top plate 'Military Stereo 6 X 30' and on the left top plate 'Bausch & Lomb Optical Co Rochester NY USA' There is a further inscription on the right top plate: 'S.1 08950' The bottom plates are each inscribed with a broad arrow. From the information given by the previous owner, the binoculars were owned by his father, an officer in the British Army in the First World War. According to Fred Watson's little binocular book, the mark S1 was applied to prismatic binoculars first grade after testing and acceptance into British Service use in WW1. Unfortunately, the binoculars are missing one screw-in eye cup. Can you advise me of any dealers in the USA who may be likely to have a replacement eyecup in stock?
With thanks Keith Shackleton
Subject: RE: Bakelite Eyecups for binoculars
From: Paul Johnston <pjohnston@___ond.com>
Does anyone know where I can obtain a supply of bakelite material? I am looking for a block in dark grey or black that I can have machined into replacement eyecups. Specifically the wartime 7x50, 10x50 Zeiss and 7x50 Leitz.