Big problems in focusing with Bessa R and russian lenses

[potomo]

Hi to all,
yesterday I have finally bought a silver Bessa R (used) and today I've shot the first film with my new camera. 😎

I have noticed that it is not possible to focus at infinity and the biggest problem is that at low distance, the mistakes in focusing are huge 🙁 .

Here you are a sample: with the j11 the distance measured with rangefinder is 7.5 m but the real distance of the subject is 5 m!! And the same problems with the other 50mm russian lenses.

I know that in this forum there is a lot of people who use russian lens and Bessa R, how can you focus correctly?

Do you think there are some problems in my rangefinder??

Thank you all very much

Potomo

 

[brachal]

I've used many FSU lenses on my R -- J11, J8, J3, I61, J9 -- and never had a problem like the one you describe. My first thought would be that you've got a poorly made or adjusted lens, but if the problem is consistent while using different lenses, it's probably the camera rangefinder. Regardless of the difference in focal standards, you shouldn't be 2.5 meters off at 5 meters.

Have you tried multiple lenses? Non-FSU lenses? Are the FSU lenses accurate on your Fed and Zorkis?

 

[mike goldberg]

Hi there potomo,

I bought a J8 specially "collimated" or modified by Brian Sweeney, for my Bessa R. It's a great lens, sharp, with a lovely bokeh. NOTE, however, that I use another FSU J8 on my Fed-2.

What Brian is trying to convey above is: A "Leica standard" camera like the Bessa R, usually requires the modified J8. The FSU camera bodies utilize FSU standard lenses [no modification], and there are lots of them.

I suggest you write to Brian before you buy your next lens... Your R/F may be OK, after all.

Good luck, mike

 

[potomo]

Here I am, I've just done some focus test with my Russian lenses over the Zorki and the voigtlander.

Over the russian camera, no problem (a few of tolerance) but the same lens over the Bessa, huge errors :-(

how can I do? Is it possible to modify something to fit my fsu lenses over the bessa?

 

[brachal]

Potomo,

I would find a way to verify that the rangefinder on the Bessa is accurate. Russian lenses are to a slightly different focal standard, but the error should be in centimeters not meters. Generally speaking, it's only noticeable at the widest apertures and short distances ( 1 or 2 meters). Try to find another LTM lens (non Russian) that you know to focus accurately, and test that on the Bessa. Given the magnitude of your errors, and the fact that it appears to be consistent with multiple lenses, I suspect the rangefinder is to blame. They can go out of alignment, especially if the camera has been dropped.

 

[potomo]

thank you, that is a good idea: next week i will go to the shop were I bought my bessa to try other lenses and I will let you know 🙂

Potomo

 

[brachal]

I've seen a wide-range of deviation in FSU lenses. About 1 in 5 were right-on, most required an extra 0.1mm to 0.2mm increase in the thickness of the shim, and the worst required an extra 3mm shim.

Check the Bessa with a camera made for the Leica, ie Leitz, Canon, Nikkor in LTM, etc before deciding it is the RF in the camera that is off.

Brian,

If he's checked 4 lenses that all focus OK on his Zorki but are 7+ feet off on the Bessa, wouldn't the Bessa be the most likely source of the error?

You know a lot more about this than I do, so I'm just seeking your wisdom here. 🙂

 

[Spyderman]

with the j11 the distance measured with rangefinder is 7.5 m but the real distance of the subject is 5 m!! And the same problems with the other 50mm russian lenses.

This probably means you were testing only RANGEFINDER versus SCALE on lens, right?

If the error is consistent with more lenses, then I'm 99% sure the RF is misaligned and it will need to be recalibrated. It is possible to do it at home, but you 'd be better letting a skilled repairman do it.

 

[pvdhaar]

I've a somewhat similar experience. When I focus the FED-50/3.5 on my Bessa and Leica, the lens scale indicates a distance significantly further than the actual subject distance. I'd have to modify the lens to correct it. Instead I've decided to close down to f5.6 and let depth of field take care of it.. Worked so far..

 

[potomo]

Ok, you are telling me a lot of good test to do with my lenses. Yesterday I've done a lot of focus and exposition test with a FP4, so in a few time I can tell you if the distance mistake is on the scale or on the rangefinder!

This morning I will do some comparative test with zorki 4 and bessa and I will let you know the results!!

 

[potomo]

Here you are the results:

I've done the test in a sunny place to obtain better focusing results. The real object distance is 4 m.

Bessa R:

J11: 5m

J8: 4,8 m

I22: 5-7 m

I61: 5 m

Fed 2:


J11: 4m (almost perfectly)

J8: 4m (perfectly)

I22: 4-5 m

I61: 4 m

Ok, the I22 has a poor scale, that's clear!

But the other lenses seems to work perfectly on the fed 2... only my Bessa has the pronlems :-(

 

[Mazurka]

The Bessas (including the R3) simply don't have sufficient RF accuracy for a 135/4 lens, even if the J11 is calibrated to the Leica standard.

http://www.imx.nl/photosite/leica/technics/rfaccuracy.html
http://www.dantestella.com/technical/compat.html

 

[potomo]

Thank you Mazurka, very interesting articles.

It's absolutely true that focusing with a Bessa R and a 135mm lens is a "bit complicated" but with my 50mm lenses (and expecially the I61 and J8) there are very huge differences (1 meter of mistakes in a measure of 4 meters!!)

 

[potomo]

Here I am with the results of the focus test.
I have finally developed the film with all the bessa photo and the short distance subject are absolutely out of focus. The same lenses with fed 2 gave perfect results. So the problems are probably in russian lens collimation.
Tomorrow I'll go to the Leica shop and I'll try some CV or Leica lenses: I will let you know.
So, how can I collimate the lenses from Contax to Leica standard?

thank you all very much!

Potomo

 

[nzeeman]

Here I am, I've just done some focus test with my Russian lenses over the Zorki and the voigtlander.

Over the russian camera, no problem (a few of tolerance) but the same lens over the Bessa, huge errors :-(

how can I do? Is it possible to modify something to fit my fsu lenses over the bessa?

if they work on zorki then it 99% that you have misaligned rf on bessa. scale focus on all fsu lenses should be universal. i never saw that big mistake in distances usualy my scale shows 1m when im on 1.1 m and thats a biggest mistake i saw.

 

[john_van_v]

Solution is simple -- get a Bessa L, and use an external rangefinder

 

[payasam]

Do what Bill says. Try a couple of non-FSU lenses on the R. If you get the same errors, the R/F is off.