Monday, May 11, 2015

Adjusting the Focus on a MIR-38B 65mm

Lately, I got myself into the KIEV 88 medium format system.
Don't ask me why....
OK, you asked, this is why: 6x6 is a square format, simplifying my photography, I thought I should give square format a chance, removing one more parameter, allowing to focus more on composition.

Right, so, that's what happened: I got this very nice kit with a KIEV 88 and 3 lenses (80mm, 65mm and 45mm).
2 of the lenses were just right. Meaning that one was not OK...
Guess what, that lens that was not OK was the one I planned to use the most... the 65mm wide-angle.

The MIR-38B 65mm did not focus infinity! Actually, it only focused up to 8m. As a secondary problem, the "DoF-preview"-lever was kinda dragging.
When purchasing the kit, I was not informed about this, however, I did not expect to receive a perfect kit either, seen the many reports about the poor quality control done on equipment of such kind.

At closer inspection, it was clear that some previous owner discovered the problem that this lens has (had). Traces of (unprofessional) attempts to open the lens are obvious.

The following image is not mine... I got it from the following link:
http://digichar.com/imgs/a/e/d/e/i/ussr_soviet_lens_mir_38_b_3___565mm_medium_format_kiev_60__6c__88cm_pentacon_six_3_lgw.jpg


On this photo, you do see some screws on the back of the lens, but if your lens is just out of focus range... don't touch any of those!

If the focus range is the problem of your lens, just (carefully) remove the rubber-sleeve from the focus ring... get it out of the way!
You will now find 3 tiny screws on the focus ring. Gently loose those, you don't want to unscrew those. Just loosen those a little.
Now, you want to mount the lens onto your camera.
Slight pumping back and forth action with the focus ring doing a left-right motion, while looking through the view finder, will get you some idea how to further proceed.
Once you figured out what I am talking about, you want to use the split-image indicator to focus a very distant object.
You done that, lock those screws again.

Now you want to unlock the screws of the DoF and focus indicator ring ans adjust the red dot to whatever position your infinity focus is.
Lock down everything.

If the focus position was you only problem (which is very likely), you're done!

With my lens, more things were wrong. The DoF-preview stuck.
Actually, I had to remove the 3 screws you see on the back of the lens. This removes a plastic shield.
Further, 3 long (!) screws of the back of the barrel will need to go out. This will remove the aperture selector mechanism, including a tiny steel ball, which you have to watch out for!
When removing the barrel, you will hear a click, which is the aperture tension mechanism.
In my lens, the preview lever was badly bent (and partly sheared off) on the inside. With a pair of pliers, I carefully bent the lever to a functional position.

I managed to get my MIR-38B 65mm lens into fully functionally shape. I hope that my little howto helps you to deal with your very own MIR lens.

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