Komura Komuranon Interchangeable Mount System: The details

philslizzy · Joined: 07 Aug 2012 Posts: 4745 Location: Cheshire, England

A very interesting and informative topic. Thank you. This should be a sticky so we can refer to it if we need to.

The interchangeable mount system is clumsy and I wonder if it originated from a factory system where the factory made lenses then attached specific mounts to them based on the market, at the customers request or even by the importer. This could explain why the apertures are on the mount and the screw-on system is used. It would be cheaper than making dedicated lenses.

woodrim · Joined: 14 Jan 2010 Posts: 4060 Location: Charleston

woodrim · Joined: 14 Jan 2010 Posts: 4060 Location: Charleston

I should have read page 1 before posting; lots of good information there.

norland · Joined: 10 Aug 2013 Posts: 165

Nicely made lens, quite lightweight and handles well ... but image quality is almost acceptable by f11. Sad

Has an M42 mount.

iangreenhalgh1 · Expire: 2014-01-07

The 1970s Komuranons are very rare here in he UK. The 2.8.28 is the most common, in that I've seen it for sale three or four times, always in Canon FD mount. The occasional zoom shows up, but other primes are almost never seen.

However, a 3.5/200 in mint condition appeared on ebay last week and I grabbed it for the massive sum of 6ukp inc postage. Arrived today, looks brand new, it has an OM mount so I'll have to get an OM-NEX adapter to be able to try it out. Beautifully made, fingers crossed it performs well too.

woodrim · Joined: 14 Jan 2010 Posts: 4060 Location: Charleston

iangreenhalgh1 · Expire: 2014-01-07

Thanks for the tips. For testing, I use a tripod and the 14x magnify assist on the NEX. I tend to find really sharp lenses are very easy to focus this way, but less than pin sharp ones can often be tricky because you're just not sure if you're struggling to find the sharpest point of focus or if it never really gets that sharp. Low contrast lenses, even if very sharp can also be tricky to focus on the NEX.

I tested a Sankor 3.9/200 I just bought in mint condition for 7ukp inc postage. It's not good, not sharp, low contrast, visible red and green CA. Most worrying, the sharpness and contrast significantly between f3.9 and f8. Light was quite good. I'll give it at least one more try, user error can always come into it of course. I hoped it might be as good as the Sankor 2.5/105 I have, which is excellent, but that seems a faint hope now.

Shutter speeds were 1/2000 at f3.9, 1/1000 at f5.6 and 1/500 at f8 so there shouldn't be any shake causing a loss of sharpness.

I might have got a lemon that was not right when it left the factory, hence it's in such good condition - it was never used after an initial trial.

No PP on these, first is at f3.9, second is at f8, with corresponding 100% crops, I hope the Komura is significantly better than this:

woodrim · Joined: 14 Jan 2010 Posts: 4060 Location: Charleston

iangreenhalgh1 · Expire: 2014-01-07

The rear glass has a very slight haze, otherwise it's clean. Interestingly, my Auto Sankor 3.5/200 also has the same haze on the rear glass.

That would reduce contrast a little, but the softness.... Sad

connloyalist · Joined: 22 Jul 2020 Posts: 345 Location: the Netherlands

Reopening a very old thread here. I am in the process of "discovering" Komura lenses. The pictures in the first post don't show anymore. Any chance they can be re-uploaded? I an very interested in what they say.

Regards, Christine