CZJ Sonnar 180/2,8 - bubbles in glass

Discussion in 'Medium Format Cameras and Accessories' started by transporti686, Aug 26, 2012.

  1. transporti686

    transporti686 Member

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    Hello,

    I bought CZJ Sonnar 180/2.8 without MC. In front glass element of this lens I see three little bubbles. Are this bubbles problem for image quality?

    I see spots in the photo with this lens. Are this spots caused by bubbles in lens? Could you see attached picture, please? Thak you very much.
     

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  2. M.A.Longmore

    M.A.Longmore Member

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    Send me the defective lens.
    I will dispose of it properly !

    As a public service to the APUG Community.

    Enjoy The Weekend !

    Ron
    .
     
  3. Slixtiesix

    Slixtiesix Subscriber

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    Even without having seen them, I think there is no chance that these bubbles will effect image quality in any way.
    Did these spots occur in other pictures as well? (Nice shot, by the way!) To be 100% sure, you can post a picture of your front element so we can have a look on the bubbles, but as I said, I would not bother but enjoy this great lens!
     
  4. Gerald C Koch

    Gerald C Koch Member

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    Optical glass is difficult and expensive to make. Hence a few small bubbles are not considered to be a defect. Artifects on the surface of a lens or interior to it cannot be imaged by the lens so you will not see any spots.
     
  5. transporti686

    transporti686 Member

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    Thank you very much. I will try this lens, again. I have only two pictures from this lens, yet.

    Second picture is here, same place, little-bit later, from same camera position on tripod, moving boat on the river, exposure time 1 minute, f16.
     

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  6. transporti686

    transporti686 Member

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    I found manual for disassembly of this lens. I cleaned glasses. I will try this lens as soon as possible.
     
  7. Richard S. (rich815)

    Richard S. (rich815) Subscriber

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    Hope you reassembled it perfectly. Personally I would have left it alone.
     
  8. Sirius Glass

    Sirius Glass Subscriber

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    I can attribute each of those spots to particular street lamps. Do not start tearing a lens apart based on one photograph, especially when a few rolls of film could thoroughly test the lens.
     
  9. transporti686

    transporti686 Member

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    Disassembly and reassembly of this lens is not very difficult. I putted down only front glass element, which is block of glasses. After removing front block there is no problem to clean other elements and elements in front block.
     
  10. transporti686

    transporti686 Member

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    :D Lens is cleaned and assembled. I will try to shoot same place and another pictures.

     
    Last edited by a moderator: Aug 26, 2012
  11. jvo

    jvo Subscriber

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    NESSIE!!!!

    :tongue:
     
  12. transporti686

    transporti686 Member

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    Last night, I was at the same place. I did two photos of same object. After inspecting negative, I see nearly same spots on the water. I think, that spots are not on water in real eveview (exposure on the film was 4 minutes, my eyes are not possible to record this long time to one frame :D). I think, that spots are from bubbles or lens flare, but I used lens shade. I want to scan other pictures from this lens and I will check spots. I will post results later.

    Sorry, for my not so good English:D.
     
  13. cramej

    cramej Subscriber

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    Those spots are not from bubbles--if bubbles cause image defects that severe, then the many thousands of Zeiss, Leica, Angenieux etc lenses that were made with a few bubbles in the glass are horribly defective and no one should buy them. Bubbles used to be considered a sign of quality in glass lenses. They are also not lens flare. If you look carefully, there are two sets of street lights that would not make a reflection across the entirety of the water as most of them do because the bridge would block part of the light. Those two lights line up exactly with the spots.
     
  14. transporti686

    transporti686 Member

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    Thank you cramej,

    it is possible, because I cant see this spots on water with my eyes when water is moving. I will check scans from other pictures.

     
  15. Sirius Glass

    Sirius Glass Subscriber

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    Sigh! As I stated in post #8
     
  16. Dali

    Dali Subscriber

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    It is very unlikely there is a relation between bubbles in the glass and the artifact of your picture as these bubblle are very far from the focal plane.

    As a side note: I always heard about these bubbles being the sign of superior glass but I never been convinced. Were they inherent to the melting process, certainly but to me they are a defect more than anything else.
     
  17. transporti686

    transporti686 Member

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    Everything is OK. On another images I dont see any spots. Thank you, all.
     
  18. benjiboy

    benjiboy Subscriber

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    These bubbles only occur in best optical glass, and are nothing to worry about.
     
  19. brucemuir

    brucemuir Member

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    I have several Zeiss ( at least one opton and one Jena) 50mm 1.5 Sonnars and 2-3 of them have bubbles.
    Back around wartime production the air bubbles were common and many attest that they in no way affect image quality.
    I've never encountered a problem with mine.
     
  20. E. von Hoegh

    E. von Hoegh Member

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    The bubbles will not cause any detectable image degradation.