my industar 69 should be here this week. Wondering what is the best solution for infinity focus.

Discussion in 'Adapted Lenses' started by colbycheese, Jul 19, 2015.

  1. colbycheese

    colbycheese Mu-43 Veteran

    378
    May 1, 2012
    Way up there.
    So i purchased a industar 69 about 2 weeks ago and it should be here in the next few days. I understand that you need modification to get infinity focus with the lens. So i know that there is the option of modifying the lens, or the adapter. What i understand is that the same method will not work on all lenses. So i am wondering what is the best, and easiest way to modify this lens for infinity focus. I was planning on buying another adapter for the lens only. The one i was getting has the adjustable inner thread ring. I know you can sand this down to get infinity focus, but how exactly does this work?
     
  2. listers_nz

    listers_nz Mu-43 Veteran

    256
    Nov 22, 2013
    Christchurch, New Zealand
    Simon
    I don't have one of these any more, but what I did was follow the instructions (posted elsewhere) to change the focus without making any physical modifications to the lens:
    • Set the focus to infinity.
    • Unscrew the three retaining screws around the focus ring and remove it by lifting it straight off. Be careful not to disturb the position of the lens block at the infinity focus setting.
    • Take a close look at the rear of the lens block. If there are exposed threads, there may be enough travel for you to get infinity focus without any major modifications.
    • Screw the lens block into the base as far as it will go
    • Slip the focus ring back on and line up the infinity focus mark.
    • Try to tighten the three retaining screws far enough to secure the focus ring flush with the front of the lens block.
    That didn't quite get me to infinity, so I modified the adapter by sanding off the back (side away from the Industar lens) of the inner ring. This works because the ring has a taper on the side of it, and the screws that hold it in pull the ring as far into the outer of the adapter as they can. So by removing material from the back, the ring fits further into the adapter, thus moving the lens closer to the camera sensor. You could achieve the same result by removing material from the front of the adaper ring, but this is the side that mates with the lens, so I chose not to mess with it.

    In theory, it might be possible to leave the lens alone and just remove material from the adapter, but I'm not sure how much you would need to remove, and it gets a bit tedious doing it with sandpaper.
     
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  3. colbycheese

    colbycheese Mu-43 Veteran

    378
    May 1, 2012
    Way up there.
    how can you get the lens to be closer to the sensor, when the lens is wider than the outer cavity of the lens adapter?
     
  4. listers_nz

    listers_nz Mu-43 Veteran

    256
    Nov 22, 2013
    Christchurch, New Zealand
    Simon
    No it isn't, at least it wasn't on mine, see:
    16220717830_572b50464d_z. GX7 with Industar-50-2 50mm by SL Pics, on Flickr
    The silver insert in the adapter is clearly larger than the diameter of the lens.
     
  5. colbycheese

    colbycheese Mu-43 Veteran

    378
    May 1, 2012
    Way up there.
    OK makes sense now
     
  6. listers_nz

    listers_nz Mu-43 Veteran

    256
    Nov 22, 2013
    Christchurch, New Zealand
    Simon
    Would also help if I posted the correct photo, but the sizing with respect to the adapter is the same. Following is the '69
    16408132205_665a1a939a_c. GX7 with Industar-69 28mm by SL Pics, on Flickr
     
  7. Turbofrog

    Turbofrog Mu-43 Hall of Famer

    Mar 21, 2014
    I did this modification just the other week, but instead of sanding away the adapter, I have access to a tiny lathe and so I machined down the protruding ridge on the inside of the lens body that the lens block screws into. This allows the lens block itself to go deeper in the body, so it will now go to infinity on any camera with a standard Leica screw mount/M39 adapter. Looks like it came that way from the factory, I'm happy. Obviously not everyone can do this without the tools, so your solution is a perfectly serviceable one.

    All told, including over-cautious disassembly, cleaning, machining of the body and grinding of the stop screws, chasing threads, re-greasing, and testing for infinity-focus, I think it probably took me 2-3 hours to do?
     
  8. CharlieL

    CharlieL Mu-43 Veteran

    237
    Aug 2, 2014
    Burkburnett Tx USA
    Charlie
    I took the two stop pins out of my Industar 69, I like it this way, I can unscrew the lens a bit to get more of a macro-ish shot and also go to infinity. I do have to be careful and not unscrew it all the way though. The 69 pretty much lives on my EPM1, I like it a lot.
     
  9. richardp

    richardp Mu-43 Regular

    93
    Jun 17, 2015
    Europe
    Richard
    Hoping somebody is still looking at this thread and maybe can advise....
    I got one of these and did the mods so it would focus to infinity. All is working fine except that it only seems to take slight pressure on the focus ring (like when putting it in my bag) for it to come loose. The ring which you use to focus is connected to the edge of an inner ring by three small screws. It seems to pop off this edge very easily. I don't want to overtighten the screws and perhaps damage the threads.

    Any advice gratefully received!

    Richard
     
  10. Turbofrog

    Turbofrog Mu-43 Hall of Famer

    Mar 21, 2014
    Hmm...that's a bit of an issue. I think you are rightfully concerned about issues with the threads. Have you tried carefully unscrewing and seeing if there's any gunk or debris in the threads that is preventing it from tightening further? Mine is quite tight...

    As a last resort, if you've made the mod successfully and have calibrated the focus ring so that it is accurate on your camera, you could glue the focus ring on with a small amount of epoxy to ensure that it won't pop off. That's obviously a permanent solution, though!
     
  11. richardp

    richardp Mu-43 Regular

    93
    Jun 17, 2015
    Europe
    Richard
    Hi Turbofrog and thanks for the quick reply.
    I already had a look at the screws and there is nothing preventing them from tightening fully. The problem seems to be that the screws have a pointed end so the point of contact with the inner disc is very small. I wondered if they were supposed to go under the disc in some way so tried that, but it just pushes the focus ring down so that it rubs against the part behind - too stiff to turn.
    Maybe I just need to bite the bullet and tighten some more.
     
  12. Turbofrog

    Turbofrog Mu-43 Hall of Famer

    Mar 21, 2014
    You could also try filing the tip of the screws slightly - another non-reversible option, but would give a larger contact area.

    For reference, and for what it's worth, all 3 screws holding the focus ring on my lens are screwed in so that their heads are below the surface of the metal. So you may indeed just need to tighten them more. Obviously you need to make sure you're using good form with such tiny screws. Constant pressure to ensure that you don't strip them.
     
    Last edited: Jan 27, 2016
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  13. richardp

    richardp Mu-43 Regular

    93
    Jun 17, 2015
    Europe
    Richard
    Thanks, some good ideas there.

    I'll wait a day or two to see what else comes up. Hard to believe that I am the only one with this problem!
     
  14. CharlieL

    CharlieL Mu-43 Veteran

    237
    Aug 2, 2014
    Burkburnett Tx USA
    Charlie
    I have not experienced the same problem. I do think that the screws would hold better with the points. I wish I had something smart to say.
     
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  15. richardp

    richardp Mu-43 Regular

    93
    Jun 17, 2015
    Europe
    Richard
    Ha ha. Thanks Charlie,
     
  16. richardp

    richardp Mu-43 Regular

    93
    Jun 17, 2015
    Europe
    Richard
    Thanks Charlie and Turbofrog for the suggestions. For now I have tightened the screws as much as I dare. As it happens I recently bought one of those artificial leather "made to fit" cases. Only it is made to fit the epl3 with the kit lens, so when I have the I69 mounted there is lots of space around it and nothing pressing against it. Hopefully this will avoid the focus ring coming off!!