The Computar lens and ULF coverage.

[Dan Fromm]

Thanks for posting this John. I've added a link to this page to my list of useful lens-related links, which can be found at: http://1drv.ms/1urNWXL

[ic-racer]

Here you go Sandy (I've got these scattered through different emails that I use to "clip" notes into...) - again, I can't remeber where I clipped it from - might have baan an ebay sale....

"The following is from the beat up information sheet, (a letter) which was packaged with my 305/537 APO-Kyvytar and in the box with the Korona.

It is not dated.

"APO-KYVYTAR lenses are made by the same people in Japan that made the convertibles under the "Computar" trademark which I used to own and which I sold to Chugai International Corporation who use the trademark for their video lenses, enlarging lenses, and the large format taking lenses (Computar Symmetrigons).

The APO-KYVYTARs are the same formula as the former Computar convertibles except that the APO-KYVYTARs are one stop faster, i.e., 6.8 instead of 9.0

The APO-KYVYTARs convert to a focal length just a little less than double the nominal focal length simply by un-screwing the front element and using the rear element.

The APO-KYVYTARs convert in focal length as follows:

>From 150mm to 264mm 210 370 240 422 270 475 305 537 360 633 480 845

The diaphragm scale is a double scale. The second scale is for use with the single rear element. The rear element alone is slightly softer and therefore good for portraits where it is desirable to shoot farther from the subject and soften the texture of the subjects faces.

Both elements together give you the sharpest picture, and flattest field, and the best color that money can buy!"

It is signed by J. Callahan, President, KYVYX Corporation, South Hackensack, NJ."

I've tried my 210 as a 370mm - it' actually pretty nice. But I have only really used it for close-ups of flowers, so the background i all out of fiocus anyway - so not really a scientific test. That said, as a 210mm lens, it's a sharp snappy little bugger

BTW - the Kowa's also become 6.8 once you put them in a shutter (I think Jim Galli forked out for a WA Kowa 6.8 only to find it was exactly the same as his barrel f9 he had, only difference was it was already mounted in a shutter...?)

I was searching for info on Copal #3 shutters and came across this image from a video. I was very curious about the lens rather than the shutter. Turns out it is a picture of a 6.8 305-537 Apo-Kyvitar.
I guess a somewhat rare lens. The only picture of it I could find and one of the few mentions of it was in this old thread.