Carl Zeiss Jena 10x50W Jenoptem binoculars.

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Lady Isabella
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Post by Lady Isabella »

David Frydman wrote:So yes Zeiss and other German firmsmake optics of the highest quality, although Taylor Hobson lenses were often better.
It is a great shame that no British firm seems to be making binoculars now whereas at least five German factories still have German manufactured binoculars.

David
I second this, some of the British made binoculars were very good indeed.
In the past week I stripped down and cleaned a 70 year old pair of WW2 Kershaw
Army binoculars. The whole job took under an hour.

With all the prisms removed, I compared the machining work against a pair of WW2 Zeiss.
The Zeiss are very nice, while the Kershaw looked a bit rough and ready, not quite the same
level of workmanship, but I guess we had other priorities at the time.

Everything was re-assembled, first look and zero collimation problems, perfect sharp image
from the off. Comparing the cleaned Kershaw against the Zeiss, I could not see any difference
at all with the view. It was as if both pairs had been made at the same factory at the very same time.

Out of interest I tested the Kershaw against several pairs of Multi-coated Jenoptems that we have
on the shelves. First off the feel and handling. no contest, the Kershaw the clear winner.
Solid in the hand and feel virtually indestructible, indeed this pair has
been dropped on more than one occasion with no lose of collimation or optics problems.

Image sharpness, Kershaw were as sharp as the Jenoptems and stayed sharper more towards the
edge of the field of view.

Brightness, a bit of a surprise here, I expected the more modern multi-coated optics to give a more
noticeable brighter image. Well the difference in daytime was so slight that it is hardly worth mentioning.
The more I look, the less of a difference I notice. I have read that Zeiss DDR started multi-coating
their optics in the late 70s and tried different methods and materials towards the end.
My Jenoptems date from the mid to late 80s.

Looking at a streetlight at night, the Jenoptems controlled the flare slightly better than the Kershaw.
and showed stars a touch fainter than the Kershaw. However the difference is not as much as I expected,
given all the formula for light loss between un-coated and multi-coated prisms.

Looking at birds and plants during the day I do not notice any difference in the views, colourful plants
looked the same level of colour and tone through both pairs.

So some excellent work on the part of this long gone British binocular maker.
Also as a side note, I found that various parts from the Jenoptems also fitted the WW2 Zeiss with no alteration
at all. Looks like Zeiss Jena were still using some of the old tooling and designs as the older WW2 models.
David Frydman
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Post by David Frydman »

Thank you Lady Isabella for your findings.
I think you will find that 12x40 Russsian or Soviet prisms fit your old Zeiss porroprisms, possibly also 12x45 or 8x30??
To be fair Zeiss E. German binoculars do not compare favourably with west German Zeiss, and Zeiss generally have their own ideas on edge sharpness and field curvature, which I don't understand. Also Leica have their own ideas on distortion and panning, which may be valid. However, I do not like the fact that top quality Leica roof prism binoculars have click stop dioptre setting, which may mean a critical observer can never get a perfect setting.
Fujinon binoculars can apparently be dropped 6ft on concrete with almost no visible sign and perfect collimation. Perhaps a lucky drop, and I have heard of Leica lenses working perfectly after a 20ft drop perhaps onto grass.
I must admit though that a 1955 Hensoldt 16x56 is a revelation in that it outresolves any modern equivalent. It is a very lightweight roof prism and in my opinion outstanding except that modern multicoatings on the very best binoculars add half a magnitude to faintest star visibility.
There are many improvements especially in medium price £100 to £200 binoculars that have filtered down from top binoculars, but there is a lot of modern junk out there.
The main problem I find with old binoculars is fungus even if supposedly water proof and many are out of collimation.
Hand made binoculars of yesteryear had a lot of loving care, whichmachines cannot equal in many cases.

The Charles Frank supplied 10x70 probably WW2 British made monocular dropped onto granite and although badly damaged still worked more or less O.K.
Not many commercial modern optics woud take that.
The specifications for military binocular did and do include drop tests, so it is not surprising they are tougher than a modern binocular for the general public.

Regards, David.

Hensoldt are of course german and were amalgamated into Zeiss and carried on as the Zeiss roof prism binocular.
Lady Isabella
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Post by Lady Isabella »

Daivd
I have some Henoldt binoculars which I find are very nice. I remember reading that Zeiss
were so taken by the Dialyt design that they went and bought shares in Hensoldt, of course over time
Hensoldt was merged into Zeiss like you say.
I think that my all time favourite binocular/ telescope maker is the work of C.P.Goerz.
A shame about the way that they were merged into Zeiss. Still at least James French (Barr & Stroud)
was able to carry-on some of the techniques and processes that he learned while at the Berlin factory.
brian livesey
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Post by brian livesey »

I had an elderly friend who once owned a pair of Kershaws. He said that the binocular body was brass, but he wasn't impressed with the optics.
One day he lost them on the moors, when the neck strap parted.
As far as I know, Kershaws were standard army issue.
brian
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