quote:
Originally posted by Brian
I advise people to stay away from the Valdai lenses, unless you are good at taking them apart. The Valdai lenses have great optics, but the build quality of the barrel and focus mount were all over the place. I've gone through Ten of them to get a really good one. Parted several out to move the optics to a ZOMZ barrel. The good one that I have required about ten hours to get working properly. The actual focus was off by 2m at 5m, the distance scale did not agree with the RF, and the helical could not drive the RF to infinity. The cure: polish down the mount, screw the helical in deeper, then re-index the focus ring. After that- reset the shim. On the Valdai lens: it was full of metal filings from the taps for the set screws. A 1975 ZOMZ "new old stock"- required a full CLA including a big change to the shim. Many of these original J-3's are in "like new condition" because not one could use them when they were new.
I should have the new J-3+ today.
Hi Brian,
how do you think about Jupiter-3 from ZOMZ Zagorsk?













