I picked up a 1958 Zorki 3C with a perfect-glass J-8 this month- with the intent to clean and shim the lens for Leica mount. Gave the focus mount the full works, including using fiber-optic polishing sheets for the finish and metal-to-metal movements. Came out really smooth. The Tabbed J-8 mounts with the three screws for the retaining ring holding the mount in are the easiest to work on, and come out the smoothest for operation. The tolerances are tighter than the 1960s lenses for RF vs actual Distance.
Got the lens shimmed for close-up, but would not focus past 10m. Th focal length was much longer than most, could not use on a Leica. SO- yesterday I used the J-8 mount for a Sonnar conversion. A very clean glass 5cm F2. Came out beautifully. Some pre-war Sonnars require you swap out the Aperture ring when screwing into a J-8 focus mount. This one did not. Once shimmed, re-indexing was simple: take out the longer set screws and use shorter ones. No need for Taps, the screws hold the mechanism against the underlying threads for the aperture ring.
Got the lens shimmed for close-up, but would not focus past 10m. Th focal length was much longer than most, could not use on a Leica. SO- yesterday I used the J-8 mount for a Sonnar conversion. A very clean glass 5cm F2. Came out beautifully. Some pre-war Sonnars require you swap out the Aperture ring when screwing into a J-8 focus mount. This one did not. Once shimmed, re-indexing was simple: take out the longer set screws and use shorter ones. No need for Taps, the screws hold the mechanism against the underlying threads for the aperture ring.
F2 and F4 Pairs.
Distance Shots- much better than the J-8.
Wide-Open at F2.
The 1958 J-8- I mounted in a 1951 Focus mount sent for spare parts, that I used for practice. Re-assembled, found enough set screws to complete it.
It will be fine for mirrorless cameras.
The 1958 J-8- I mounted in a 1951 Focus mount sent for spare parts, that I used for practice. Re-assembled, found enough set screws to complete it.
It will be fine for mirrorless cameras.
dexdog
Veteran
Looks like a good lens, Brian!
It's difficult to find the 5cm F2 with clean glass- after 20+ years, maybe one in ten? This one is nice, and has a good bloom. I need to put a yellow filter on it and try with the M Monochrom.
boojum
Ignoble Miscreant
That has to be the most photographed fence post in the world and surrounding territories. ;o)
Miles.
Beamsplitter
I’d say 1 in 100 but maybe I’m just unlucky. 😂
boojum
Ignoble Miscreant
Guys, it may just be part of my incredible run of luck but the Contax II has a 5cm '36 f/2.0 CZJ that seems to my amateur eyes to be clean. I just pulled it off the camera and peered through it. This may just be another example of the Dunning-Kruger effect. I will not know for sure until I send in a roll of film for processing and scanning. You can be sure that it is wearing a UV filter to be sure that it stays safe. And it has passed through Oleg's skillful hands for a camera and lens CLA.
The Contax III will go off to Oleg after the next Portland camera meet. It has the standard III lens, CZJ 5cm 1.5 and this one has factory coating. And if the coating is intact I think it is safe to assume the front element is fine. Is it possible the rear element is coated or do my eyes have wishful seeing?
dexdog
Veteran
I have seen quite a mix of coated CZJ lenes that are not T-marked. Some are coated on all surfaces, while others may have only the fronter-most surfaces coated, while the rear triplet may be uncoated.
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boojum
Ignoble Miscreant
Thank you.
dexdog
Veteran
Really good color saturation for an old uncoated lens. You chose well
Bright, Sunny Day. I took this lens out for a second test- this time on the Leica M240. The focus via RF agrees perfectly with the EVF. I used the M8 to test the focus when shimming this lens. I have the M8 and M240 "Tuned" to my M9, which has been used to shim lenses for many Leicas.
"Stupid Brick Wall test" at F2 and F4,
Followed by the slat Test, F2 and F4.
And of course the Fence Post,
F2 and F4
"Stupid Brick Wall test" at F2 and F4,
Followed by the slat Test, F2 and F4.
And of course the Fence Post,
F2 and F4
Color test... at F2.
This is an uncoated lens, but Bloom (oxidation) acts like a lens coating. Remember- Lens coatings were first pursued as a method of artificially introducing Bloom to a lens and not having to wait 50+ years for nature to do it for you.
This is an uncoated lens, but Bloom (oxidation) acts like a lens coating. Remember- Lens coatings were first pursued as a method of artificially introducing Bloom to a lens and not having to wait 50+ years for nature to do it for you.
At F4,
boojum
Ignoble Miscreant
Brian, The Pied Piper of Dresden. ;o)