Lens fungus

Discussion in 'Large Format Cameras and Accessories' started by photobackpacker, Apr 7, 2005.

  1. photobackpacker

    photobackpacker Advertiser Advertiser

    Messages:
    430
    Joined:
    Mar 21, 2005
    Location:
    Minnesota
    Shooter:
    4x5 Format
    I shoot mainly in the upper midwest where your equipment will actually frost over when you come in from a long outdoor winter shoot. To avoid this, I put my entire LF backpack in a plastic bag and allow it to warm up before unpacking it.

    Among the many problems this condensation could cause, I worry about lens fungus. To be truthful, I don't know anything about lens fungus, except that I don't want it!

    • What conditions cause it to form?
    • Where on the lens does it usually form?
    • What does it look like?
    • What is the best way to prevent it?
    • Are there any authoratative articles or literature on the subject?

    Thanks
     
  2. Brook

    Brook Member

    Messages:
    94
    Joined:
    Mar 12, 2004
    Shooter:
    8x10 Format
    Im sure others can give a more complete answer, but up here in the tundra, I dont think we have a lot to worry about if you keep them in a dry enviornment, like not keeping them in a sealed damp case or basement. I have only seen fungus on pretty vintage stuff or wet basement victims. If you see moisture between the elements, leave it in a warm, not hot, dry place.
     
  3. John Koehrer

    John Koehrer Subscriber

    Messages:
    6,203
    Joined:
    Apr 3, 2004
    Location:
    Montgomery,
    Shooter:
    Multi Format
    Blaughn,
    Usually forms on inner elements.
    Warm, humid storage will encourage formation.
    Almost looks like a root system from a tree, although (obviously) on a much smaller scale. Usually appear silverish in color.
    Prevention is easy, store in a dry space. You can use a silica gel to help absorb moisture. Temperature isn't important since fungus will form just about anywhere here in the states.
     
  4. Carol Flutot

    Carol Flutot Member

    Messages:
    73
    Joined:
    Mar 28, 2005
    Location:
    Whittier, Ca
    Shooter:
    35mm
    Hi,

    If your lenses are being subject to continuous condensation, you may have to worry more than just lens fungas, moisture can collect and cause rust on any metal parts too.
    Fungus can appear anywhere on the lens surface and will look like a fog or little crystal
    webbing, that doesn't go away, after they have been dried out.
    Moisture causes the fungas!
    If you do notice any fungas on your lens it is best to get to taken care of ASAP before
    it starts etching into the coating and the glass!

    Carol
     
  5. JG Motamedi

    JG Motamedi Member

    Messages:
    472
    Joined:
    Dec 18, 2004
    Location:
    Portland, OR
    Shooter:
    Large Format
    In addition to fungus, I had a problem a few years ago in which condensation between lens elements in reaction with the rare-earth elements of glass created, as John Van Stelton decribed it, "a corrosive cloud" which started to etch the glass. Luckily I caught it early before it ruined a wonderful lens.
     
  6. colrehogan

    colrehogan Member

    Messages:
    2,016
    Joined:
    May 11, 2004
    Location:
    St. Louis, M
    Shooter:
    Large Format Pan
    I should be getting a lens back today from being repaired (it also had some fungus which had etched the glass).
     
  7. Bruce Osgood

    Bruce Osgood Membership Council Council

    Messages:
    2,606
    Joined:
    Sep 9, 2002
    Location:
    Brooklyn, N.Y.
    Shooter:
    Multi Format
    This is a question for our member Carol Miller:
    flutotscamera@earthlink.net

    As far as I know if you've got fungus you keep it. It can be removed but comes back again, maybe a year later.
     
  8. Carol Flutot

    Carol Flutot Member

    Messages:
    73
    Joined:
    Mar 28, 2005
    Location:
    Whittier, Ca
    Shooter:
    35mm
    Hi Bruce,

    I have been removing fungus for a long while for folks and once I remove it
    they haven't brought them back for further cleaning. Than again, I am out here in Southern California, so fungus isn't a big problem and once it's cleaned it is not really subjected to humidity, ect. that causes the fungus.

    So I can't tell you want happens, if it's the same fungus or new fungus that comes
    on from further exposure to moisture.

    Most of the fungus cases I get are from items that were stored improperly for long periods of time or were purchased with this problem.
    So that is my experiance with fungus, I am positive that those repair folks living in mid & east coast would have more knowlege than I in this area.

    Carol
     
  9. Bruce Osgood

    Bruce Osgood Membership Council Council

    Messages:
    2,606
    Joined:
    Sep 9, 2002
    Location:
    Brooklyn, N.Y.
    Shooter:
    Multi Format
    Hi Carol

    I hadn't considered there was more than one kind of fungus, makes sense that there would be though. Kind of a regional thing I guess.
     
  10. roteague

    roteague Member

    Messages:
    6,671
    Joined:
    Jul 15, 2004
    Location:
    Kaneohe, Haw
    Shooter:
    4x5 Format
    I think you are right, all my lenses now have some form of fungus, which they never had before I moved over here.
     
  11. Dave Dawson

    Dave Dawson Member

    Messages:
    178
    Joined:
    Feb 15, 2009
    Location:
    London UK
    Shooter:
    Medium Format
    I have been told that if a lens has fungus and is placed in a dry sunny place for a few days the fungus dissapears or is that an old wives tale?

    I think the theory is that the uv kills the fungus?????

    If this is a load of rubbish please be gentle with me!!!!

    Cheers Dave
     
  12. eddym

    eddym Member

    Messages:
    1,927
    Joined:
    Jan 22, 2006
    Location:
    Puerto Rico
    Shooter:
    Multi Format
    If the fungus has already etched the glass (which, by the time you notice it, it usually has), then you can kill and/or remove the fungus, but there is nothing that can be done about the damaged glass.
    This is the sad voice of experience speaking.
     
  13. mrmekon

    mrmekon Member

    Messages:
    47
    Joined:
    Apr 11, 2009
    Location:
    Atlanta, GA
    Shooter:
    35mm
    UV will kill the fungus spores so it won't continue to grow, but it won't magically clean up what's already there. I've been wondering if a full-spectrum fluorescent bulb gives off the right UV wavelengths to kill it. Would periodic flooding under UV lamps be a good preventative measure?
     
  14. ic-racer

    ic-racer Member

    Messages:
    7,389
    Joined:
    Feb 25, 2007
    Location:
    Midwest USA
    Shooter:
    Multi Format
    This is one of the best monographs on lens fungus that I have read. It has no references though. The writer is Gordon Ian Stalker BSc, who I believe is a camera technician rather than a mycologist.
    http://www.mypentax.com/Fungus.html