Industar-69 Easy Infinity Focus Fix

This is my fix for the Industar-69 28mm 1:2.8 pancake lens famous infinity focus problem. I read several tutorials and pieced them together and came up with this non-destructive hack that still allows an infinity stop and close focus stop with only one minor setback of the aperture scale mark.

I used a digital camera for this fix which I suppose 90% of the uses for this lens is but, if you have an old 35mm film camera with the M39, Leica screw mount (with a hinged or removable back plate) you can use this lens too, just use a frosted glass plate of some kind, a removable SLR focus screen works good, or I’ve even used scotch tape pulled tight over the film guides to focus test lenses.

simply loosen (not remove) the three set screws on the side of the focus ring and lift off ring.

remove the stud near the bottom of the lens, (red arrow) it is the close-focus stop. leave the stud in the focus ring and the top stud next to the red focus mark (red circle) it is the infinity stop.

As mentioned above, leave the top stop-post and the post in the focus ring but remove the lower post.

screw in the lens group clockwise all the way until it stops. do not force.

turn the lens over and clean any grime and grease that gets pushed out while the lens group is screwed in. we don’t want any of this falling on the sensor.

mount the lens on the camera. with the aperture wide open, now back the lens group out (counter-clockwise) slowly until you see it is focused at infinity.
When you get the lens group where you want it, gently put the focus ring back on with the studs touching for the infinity stop and the infinity mark and red arrow are lined up. carefully tighten each set screw until the focus ring is secure.

all set! now the lens stops at infinity and it will stop the other way around now too but a much closer focus is now possible.
But wait! the aperture scale doesn’t line up with the red dot any more (red arrow). I simply made a new mark with a 1/16″ drill bit and painted it red and covered up the old mark with my silver sharpie.

The lens top won’t be pointing up, even before this fix because the depth of the mounting thread group is shallower than a standard M39 lens. This lens was originally on a Soviet¬†CHAIKA half frame camera. The lens could also be mounted on an enlarger.

Here are a few images taken with this lens.

Redmen’s Hall, Jacksonville Oregon ¬†@f/11. pretty good clarity.

some milkiness to the original, fixed here (above)

Redmen’s Hall back. wide-open @f/2.8 note the edge focus and there is some flare on the reflections

(above) This led me to believe the elements themselves needed to be cleaned. Indeed, I removed the rear element and with my loupe, found tiny spider-web fungus on the rear element of the front group just in front of the aperture blades, (a usual spot) I cleaned it with a 50/50 mix of hydrogen peroxide and household ammonia (put some on a Q-tip, wet area, let set 5 min. wipe dry, clean with fresh water, repeat if nec.)

in some cases the fungus had no effect, this is a nice clear shot.

This is a fun little lens. It is said that it’s glass is modeled after a Tessar. Great quality and uber cheap. I got mine on eBay from the Ukraine for $28 with free shipping. I could have got it cheaper but you want sellers with good feedback from Ukraine and Russia.




5 thoughts on “Industar-69 Easy Infinity Focus Fix”

  1. I did so; focusing is now capable to focus 2 metres instead of less than 1 metres away, but not infinity, except when stopped down to F16

  2. make sure you got the correct studs removed/not removed, RE-READ STEP 5 CAREFULY… While it’s on a camera you should be able to focus to infinity and even beyond get the lens group to infinity and then do the focus ring lock

  3. My Industar-69 wasn’t this easy to fix.

    It seems like the threading doesn’t go deep enough on all copies of the Industar-69. When focusing towards infinity, the lens group moves towards the camera. The threading of my lens didn’t let the lens go far enough to focus on infinity. This is the same problem as Uwe describes above.

    I resolved it by filing away the edges of the female part of the threading, using a Dremel or other such tool. This lets the lens group go deeper into the camera.

    However, the next issue is that when attaching the focus ring, it jams against the rest of the lens because the ring is now deeper in the camera, so I had to file away part of the focus ring stud, and put a piece of paper between the focus ring and the lens group.

    Very fiddly and definitely not “non-destructive”..

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