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Nostalgia; The high quality 7x35 and 8x40 (1 Viewer)


The simplest answer is that you have a mislabeled 9x35A. It used the 8x30 wide field eyepiece in combination with the 7x35 objective lens. One easy way to tell is to place the 8x30 to one eye and the "7x35" to the other. You don't need to look at anything, just point the binoculars at a blank wall. If the circles made by the field stops are the same size then you have the 9x35, since both it and the 8x30 share the same eyepiece and have the same size apparent field of about 64*. If the field circle of the "7x35" is much smaller, then it really is the 7x35 which used a simple eyepiece with an apparent field of only about 51*. Also remember that you can't use the field width to judge the magnification. An object that fills the narrow 7x35 field will have have room to spare when viewed through the wide field 8x30.
Thanks very much for that, Henry. I've not had a chance to compare them as yet, but I shall do so tomorrow and let you know the result... Jim.
I guess it is a nostalgia day form me. What ever happened to the "alpha" quality 7x35 and 8x40 binocular?

Disappeared from the market because not enough people bought them. They realized that 8x30, 8x32 were more useful. I can't say that I have ever seen a high end 8x40. Vixen/Celestron made some nice ones in the Ultima series but I don't know how you are defining alpha binoculars.
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Well, Henry, I did as you advised and it seems I have the 9x35, although marked "7x35". The circles made by the field stops are the same size: if the "7x35" had been smaller I'm sure I'd have noticed. Not only does the target image look larger in the "7x35"(9x35), it's also a more relaxing 'big view' than the 8x30. To my eyes, although they both appear to have the same (or very similar) 'breadth of view', the 8x30 seems more 'constraining', if that makes sense (it probably doesn't!). FWIW, the 8x30 Nippon Kogaku is a 'J.PAT.'.
One of them was a Carl Zeiss 8x40 'Deltarem' had a 11.2 degree FOV. Late 1930's. I have read the prisms were very big, and binocular was nearly 10" wide!
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I have a Romania IOR 8x40 porro prism binocular which I would consider getting towards 'Hi-end'.
IOR has been making quality optics since the mid 1935. They are also know for their rifle scopes.
These binoculars were built in collaboration with Carl Zeiss and they display excellent build and optical qualities. The body is made of steel and has a heavy rubber armor covering. They have a strong military feel to them. They are designed to operate in 'extreme' conditions. The lens are Schott with T3 multi coatings. IOR state a 98% transmission rate. They are W.P. / nitrogen filled with Back-4 prisms. The FOV is a generous 8.5 degrees and the great majority of the image is very usable. The image is flat, 3D like and tack sharp to 90% of the edge when mild field curvature becomes noticeable. They are heavy at 32 Oz. The E.R is 20 mm. The oculars measure a large 22 mm. Eye comfort is excellent with semi horned rubber eye covers. There is no blackouts or jelly beaning to the image. They are IF which may negate them as pure birding binoculars. The image does have a mild yellow / amber tinge which is typical of this genre which again may will affect color fidelity. They do give that compelling and high resolution image that only quality binoculars can display.
These binoculars are worth seeking out on the various world wide markets and go for around 300 - 400 Euros.

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Yes my apoligies. I did mean the IOR 7x40. I should have payed more attention. I should remove my post it as its not a 8x40 ! It's still a nice binocular however. Sorry again.

I should remove my post it as its not a 8x40 !
As a certain tennis player who beat a New Zealander by the name of Chris Lewis in a Wimbledon final might say : "You cannot be serious". I agree with Alexis in post #4 about 8x40 being too close to 8x42 for the difference to be interesting; unlike 7x40.
I like the way in Scott Powers' review (Holger provides a link) he seems astounded by the magnitude of his (no doubt long-suffering) wife's endorsement of them : she actually thinks they're worth keeping :eek!:|:D|
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