1. Reminder: Please use our affiliate links for holiday shopping!

Lens barrel (tube) wobbles?

Discussion in 'Adapted Lenses' started by daffy, Mar 2, 2016.

  1. daffy

    daffy Mu-43 Regular

    30
    Feb 15, 2015
    I just entered into the exciting world of adapting an old m42 lens.

    The lens I have, an Auto Rikenon 1:1.4 55mm (Ricoh Auto Rikenon 55mm F/1.4 - Review, specification and sample photos - AFLenses.net), mounts reasonably well onto the (cheap adapter) and sits tight inside the adapter. The lens seems to have a lot of metal.

    Unfortunately, the lens barrel of this fixed focal length itself seems to have an enormous amount of play - it can be pulled back and forth (about 1mm), wobbles quite a bit when touched (or used). This is easily visible in 14x magnification mode; the focus plane keeps shifting. The aperture ring, on the other hand, sits perfectly nice.

    The seller described the lens as being in good state. That does not seem to be right to me.

    Any comments on what these lenses should be like?
     

    Attached Files:

  2. carlosfm

    carlosfm Mu-43 Veteran

    230
    Oct 3, 2015
    Lisbon, Portugal
    That is not normal at all for any lens.
    You've got a lemon.
    Lesson: if you have a lemon, make lemonade.
     
  3. GRID

    GRID Mu-43 All-Pro

    Jun 22, 2011
    Try tightening all the screws you can see on both lens and adapter, that have helped me sometimes.
     
  4. Klorenzo

    Klorenzo Mu-43 All-Pro

    Mar 10, 2014
    Lorenzo
    What is wobbling exactly? The lens mount, the pairing with the adapter, the adapter to camera pairing, the focus ring, etc? Test each piece alone, and each pair at a time. Also inspect the lens mount to see if it is flat, bended, etc.

    If the lens mount is moving maybe tightening some screws could fix it. If is the adapter/lens contact zone, the m42 thread, maybe something is blocking and it does not fully seat. Maybe some kind of gasket with paper or plastic could help (even if this may mess with flange distance and infinity focus in particular).

    Reading the post again the problem seems with the lens itself. If so you may consider disassembly and cleaning the lens:



    (this is not a full disassembly, just to give you the general idea. See the next video for full disassembly (of a different lens), but maybe you do not need to go there).

    You need a spanner wrench but you can built a custom one grinding a small metal plate to the right size/shape (make sure to leave a lot of clearance from the front element). Or you could try to use a lens cap like in this video:

    The big problem, if you are considering the disassembly idea, is that if some internal parts are damaged or missing can be quite hard to come up with a simple fix/solution.
     
  5. daffy

    daffy Mu-43 Regular

    30
    Feb 15, 2015
    Good point! I had a look and all screws seem to be tight (already).
     
  6. daffy

    daffy Mu-43 Regular

    30
    Feb 15, 2015
    Great find on Youtube for the Rikenon :)

    Indeed - it is the lens itself. There is no instability whatsoever on the camera side of the adapter, on the lens side of the adapter, on the aperture ring. It is the barrel itself that is moving.

    I have uploaded a movie into my directory rikenon_lens_wobble which contains "Wobble.avi", at 380 KB size. This little movie demonstrates the effect. No effort is required to get the barrel to move.

    I'd be curious to the potential root cause of this - was the lens dropped while attached to the camera? Bad build quality right from the outset? Is this expected with age?

    FWIW, the seller has offered to take back the lens and refund the money in full. This way I will be out only my cost of getting this back to him.
     
  7. Klorenzo

    Klorenzo Mu-43 All-Pro

    Mar 10, 2014
    Lorenzo
  8. daffy

    daffy Mu-43 Regular

    30
    Feb 15, 2015
    You are good with Youtube ;)

    The lenses were/are not worth bothering with a whole lot.

    The Rikenon 55/1.4 was extremely soft at 1.4 and only started to become useful around 5.6. Plus, as I discovered, it had one bad scratch on the back lens element and some minor ones back and front. Paid about USD 15 for that, on the hope of a "magic Tomioka lens" (http://www.pentaxforums.com/forums/...-archive/277591-ricoh-rikenon-55-1-4-m42.html).

    I got also a Carenar 135/2.8 in the same package - incidentally with the same type of barrel wobble. And the quality of the lens was just awful (not that I expected _much_) - got this thrown in at USD 8.

    But, well, both lenses will go back shortly and I will try to go upmarket a bit: I just lost an auction on a package of three Contax Carl Zeiss lenses:
    • Distagon T* 28/2.8
    • Planar T* 50/1.7
    • Sonnar T* 135/2.8
    (and there was a Contax camera with winder and flash attached, too) - this pack went out at USD 315. Upcoming is a package of Contax Carl Zeiss T* 28/2.8, T* 50/1.4, and Tamron 90/2.8 SP Macro 1:1, again with a (working) Contax camera attached. Let's see ...
     
  9. Klorenzo

    Klorenzo Mu-43 All-Pro

    Mar 10, 2014
    Lorenzo
  10. daffy

    daffy Mu-43 Regular

    30
    Feb 15, 2015
    Excellent tips!

    I have my budget set, and I am using an auction market other than ebay (which is the local player - ebay does not play any role here, although they try). Time will tell.

    In the meantime, I keep staring at the parcel tracking for my dirt cheap Fujian CCTV lenses coming straight from China ...