Swapping lenses in Bessa rf

[Bessafan]

Hello, that's my first post so thanks alot for letting me in
I've got a peculiar problem, recently I've accuired a very beaten Bessa RF, I got it for free just because I had use for some parts- I'vw already had one Bessa but it missed the original filter and case. When I brought it home I realised that it has a better lens than mine (mine had the cheapest Helomar, the dead carcas had Skopar). I screwed it apart and discovered that there were no diffirences whatsoever between the shutter comparaments, not even distancing shims. I decided to try and upgrade my old bessa and swapped the lenses. Today I've developed the film and unfortunately the photos don't seem to be perfectly in focus, it could be due to the fact that I was using rather large apertures to check if the camera was focusing properly. Has anyone of You tryed anything like this and ran into similar problems?

 

[Alex Varas]

I have had or passed by my hands about 5 Bessa RFs with all lenses, I did the change of the Helomar for Skopar but I checked with a ground glass that infinity setting was ok, you maybe need to add or remove shims.
If with shims you can’t because infinity lays before the shutter plate holder then you have to mess around with the focusing knob and I don’t recommend it unless you have some experience adjusting the rangefinder later.
And checking at the widest aperture is fine, with Skopars at the center should be sharp enough to see if you nailed the focus.

 

[Bessafan]

Thanks, I sure hope that the Skopar is at least sharper than Helomar
If there will be need to add shims, where should I place them? The Skopar did show sings of front focus- the image of objects that were definitely at the "infinity" was sharp just before the scale ended. I'm beginning to wonder if it won't be easier to adjust the rangefinder. It needs some vertical aligning anyway. But I don't want to touch the leatherette beacause the oil paint on it is very brittle and I definitely won't be able to preserve it in it's original state

 

[Alex Varas]

First set up the lens at infinity correctly, then adjust the rangefinder.
Shims go between the shutter and the shutter holder plate.
Check this out, it will help you to get an idea how the camera works:
http://photographytoday.net/forums/viewtopic.php?f=31&t=1463&p=8969&hilit=Bessa+rf#p8969

I would keep Helomar, they are very nice lenses.

 

[Bessafan]

I would keep Helomar, they are very nice lenses.

Really? That's literally the cheapest/worst lens this camera was made with...

 

[gone]

I'm pretty sure that Voigtlander didn't make a "worst" lens. The budget Helomar is actually a very good 3 element design, you just have to stop it down. MF cameras need to be stopped down quite a bit anyway, at least compared to 35mm. The RF is a fantastic camera, and really well built.

I was used to shooting Heliar lenses on them and was surprised to see that the Helomar even had a little bit of the Heliar's 3D look. The Skopar is sharper, but the Heliar is the top of the line w/ Voigtlander cameras. You can shoot that one wide open and make beautiful portraits.

Yours is either not focusing correctly or is hazy inside. All the uncoated Voigtlander lenses need a good hood, and a Y fltr will add some nice contrast w/ B&W.

 

[Bessafan]

Yours is either not focusing correctly or is hazy inside.

Both are squeaky clean- cleaned them myself. I only hope that the front plane isn't bent by any chance. My first photos were quite satisfying. Well..., better is an enemy of good. I'm gonna stick with the Helomar for now, tomorrow I'll take him for a walk and see if everything would function properly

 

[darinwc]

just a plug.. if anyone has a Bessa parts body.. not working but not abused.. bad shutter/lens OK. -Let me know. Ive been looking for a project.

 

[darinwc]

But to answer your question.. I would assume that the 3 lenses for the bessa rf all have the same focal length and flange to film distance. They are all 105mm.

And just to be sure.. you swapped both the front and rear lenses right?

To test, you can use a piece of vellum.. translucent paper. cut it to size like a strip of film. Use a little tape to hold it in place where the film would be.
Then set the shutter to bulb. (a locking cable release works best for this) while the lens it open, focus using the image as best you can on the paper. Then check the rangefinder and see how accurate it is.

 

[Alex Varas]

just a plug.. if anyone has a Bessa parts body.. not working but not abused.. bad shutter/lens OK. -Let me know. Ive been looking for a project.

What parts do you need?
I have something that you may use, also in local market there is one body without lens/shutter that might be ok.

 

[Bessafan]

Obviously I've swapped both rear and front elements. I've used a ground glass from my Mamiya instead of paper- it's way more accurate. I think the Skopar will need some shims to work well enough with the rangefinder. I've checked that focusing on a given distance with a rangefinder the image on ground glass was close to sharp but not quite enough. For now I've reinstalled the Helomar, it's not worth the hassle

 

[StevenG]

I don’t think Voigtländer made different bodies for different lenses. Extra shims would not help. Probably the rangefinder needs to be adjusted accordingly.