Two Weird Things About Old Lens (Vivitar 20mm f3.8)

Discussion in '35mm Cameras' started by Greg Lovern, Nov 29, 2003.

  1. Greg Lovern

    Greg Lovern Guest

    I just bought an old lens on eBay, and there are two strange things
    about it I don't understand. I hope someone here can enlighten me.

    BTW, the lens is a Vivitar 20mm f3.8, M42 mount (Pentax/Universal
    screwmount). I don't know how old it is, but its construction reminds
    me of a Super-Takumar I have. All-metal construction -- no plastic or
    rubber anywhere I can see. The front says "AUTO Vivitar WIDE-ANGLE
    20mm 1:3.8 No. 22202300". My guess is it might have been made in the
    1960's?

    First Strange Thing:
    ====================

    When I first looked into the lens, I saw a whitish haze around the
    perimeter of one of the interior glass elements, and my first thought
    was that it might be fungus. But if I look carefully with a
    flashlight, it seems to appear and disappear depending on how I aim
    the light -- I aim one way, and the haze seems almost opaque; then I
    aim the flashlight a slightly different way, and the haze seems to
    disappear completely and the glass looks completely clear.

    When I aim in a way that makes it appear, it seems to have a very
    precise border -- the haze area extends from the perimeter of the
    element to a precise circular border on the lens.

    I'm wondering if it's actually a reflection of the interior wall of
    the lens. It's really hard to tell since everything in there is so
    distorted (20mm wide angle lens). I can sort of see a narrow band
    inside the interior wall that looks sort of like what I see on the
    lens.

    What do you think? Harmless reflection, or fungus, or....?

    Second Strange Thing:
    =====================

    After scrutinizing it with the flashlight for a while, I noticed a
    doughnut-shaped, iridescent haze. It seemed to be on the interior side
    of the front glass element. The more I looked at it with the
    flashlight, the bigger it got. When I put it down for about 10 - 15
    minutes, it disappeared. Then reappeared after using the flashlight
    again. Then disappeared again.

    The flashlight is a "Mini Maglite", if that matters.

    What is that haze? Is it a problem that I should make me consider
    returning the lens?


    Thanks for any suggestions...

    Greg
     
    Greg Lovern, Nov 29, 2003
    #1
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  2. My wife, whose a nurse, suggested you ask your doctor to take you off of the
    lithium, and put you on elivil for a while......
     
    William Graham, Nov 29, 2003
    #2
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  3. Greg Lovern

    Bob Monaghan Guest

    there are some online photos of lens fungus, see links at
    http://medfmt.8k.com/bronlensfaults.html for sample links etc. The bad
    news is that you are unlikely to be able to get repairs, so if it is
    fungus, keep the lens in silica gel and zip lock bag dry environment; some
    exposure to solar UV may also help per some posters with the older lenses
    (which don't have UV cured glues), see http://medfmt.8k.com/mf/fungus.html

    most early vivitar 20mm lenses from the 1960s are not great by today's
    standard, but may be alright for non-architectural work etc. Try it out
    and see if it works, or if there are problems on film (which I would not
    expect, it takes a lot of fungus to cause visible problems on film ;-)

    lots of more modern lenses will be better performers in the very wide
    range, see my page on low cost options at
    http://medfmt.8k.com/bronwide.html and mf/kievwide.html

    if you are still worried, consider returning the lens; for $100 or so, you
    can buy a new wide or ultrawide lens with a lot better performance in M42
    mounts (cf kiev options)

    hope this helps bobm
     
    Bob Monaghan, Nov 29, 2003
    #3
  4. Greg Lovern

    Greg Lovern Guest

    Hi William,

    Thanks for your helpful post. What would we do without your expertise?

    Greg
     
    Greg Lovern, Nov 29, 2003
    #4
  5. Greg Lovern

    Greg Lovern Guest

    Hi Bob,

    Thanks for the information and links. My lens doesn't look anything
    like the fungus pictures.

    I looked through the lens from the rear, and was unable to find any
    trace of the haze. I also found an old online advertizement for the
    same lens, in which the seller describes the same strange haze. I'm
    confident it's just a reflection from the interior wall of the lens.

    Regarding the doughnut-shaped, iridescent haze, I left the lens out on
    a shelf last night without the lens caps on. This morning I held the
    flashlight to it as before. No haze formed this time. Earlier
    yesterday, I had given the lens a long and thorough (but very gentle
    of course) cleaning. This is a wild guess, but maybe some lens
    cleaning fluid seeped through and became a vapor inside the lens.
    Since it isn't happening now, I'm not going to worry about it.

    I haven't had a chance to test the lens with a roll of film; things
    are a little crazy here with a baby due any day now.

    Thanks for the suggestions on other lenses. Money is tight, and this
    one was very cheap. When I was digging for comments on it before
    bidding on it, I found one comment that it was much better than the
    current Vivitar 19mm. Is that not the case?

    BTW, I can't seem to find your kievwide.html page. What's the full URL
    for it?


    Thanks,

    Greg
     
    Greg Lovern, Nov 29, 2003
    #5
  6. Greg Lovern

    jriegle Guest

    It could be something is going on with the material used to cement the lens
    elements together. It could be crystalizing in an area around the edge due
    to a reaction with the pollutants and moisture in the atmosphere. It could
    be microcrazing as well. If you see a faint rainbow spectrum patteren in the
    haze, it could be any one of these. I don't know the exact nature of the
    cementing material, so I'm just guessing here. Fungus has a stringy mini
    spider web like appearance. As you said it could be a reflection.
    Beats me. Are you sure it is not just an interenal reflection off of one of
    the elements? Shining a bright light into a lens will cause all sorts of odd
    reflections that move, change and vanish as you move the light and change
    the viewing angle.

    Inspecting a lens with a flashlight tends to cause people to over react as
    it makes the tiniest bits of dust glow like a star in the night sky. Hold
    the lens up to a window (not in the sun) and look through it. If it does not
    look too hazy or dusty, it will probably perform just fine.
    John
     
    jriegle, Nov 29, 2003
    #6
  7. Well, you have to admit....It was free.......
     
    William Graham, Nov 29, 2003
    #7
  8. BTW, the lens is a Vivitar 20mm f3.8, M42 mount (Pentax/Universal
    Greg

    Your lens was made by Kiron, (Kino Precision Industries) in the early 70's.
    Beig a Kiron built lens, it is most likely, very well made. And has very good
    glass.

    QLP
     
    Quietlightphoto, Dec 11, 2003
    #8
  9. Greg Lovern

    Greg Lovern Guest

    Hi QLP,

    Thanks for the information.

    I was finally able to do my usual round of (informal, real-world,
    non-chart) round of test shots, and I also was able to get several
    indoor shots at the hospital while my wife was in labor, and
    afterwards while our baby was in intensive care (everything turned out
    fine, and our new son is now home with us and doing great). (BTW,
    fortunately I was not the primary photographer at our son's birth; a
    friend handled that.)

    I'm very happy with the pictures; they turned out better than I had
    thought they might. I've never used any other lens that wide, so I
    don't really have any frame of reference for comparison, but the
    pictures were very sharp edge to edge (except when it was my own
    fault), even wide open, and the color looked good to my amateur eyes.
    There was a fair amount of distortion at the corners, but again I
    don't know how this compares to other 20mm lenses. From my test shots,
    I decided that as long as I kept human heads out of the corners, it
    was fine. Also, structural corners (such as window corners, etc.) in
    the corners of the frame would get pretty stretched, but not to the
    point of ruining a shot.

    I was especially pleased with the sharpness. It's sharp enough to be
    acceptable even in an inexpensive normal lens, though my Pentax-A
    50/1.7 is somewhat sharper.

    The least desirable thing about the lens for me is simply that it's a
    screw mount. I wonder if its mount can be swapped out for a Pentax K
    mount, maybe from a dead, parts-donor lens?

    Thanks,

    Greg
     
    Greg Lovern, Jan 4, 2004
    #9
  10. Greg Lovern

    Jeremy Guest

    Not a problem. You can buy an adapter that will mount the screw mount lens
    onto a k-mount camera. They cost about $20.00 and are available on eBay and
    at photo dealers.
     
    Jeremy, Jan 5, 2004
    #10
  11. Greg Lovern

    Greg Lovern Guest

    Hi Jeremy,

    Thanks, but I already have that adapter. What I meant is that the
    adapter is very fiddly. It's even harder to get off of my new Pentax
    ZX-L than it is to get off of my Pentax Super Program. It wouldn't be
    too bad if I was by myself doing landscapes, but more often I'm with
    my impatient wife and wailing newborn, trying to get what shots I can
    before she rebels. That isn't a great time to fight with an adapter
    that doesn't want to come off.

    I've tried removing the locking tab from the adapter, so that the
    adapter stays on the lens, turning the lens into a non-locking bayonet
    mount with stop-down metering. That's more convenient -- without the
    locking tab, the adapter isn't fiddly at all -- but it means
    dedicating an adapter to that one lens (and getting another adapter
    for other screwmount lenses), and getting a new rear lens cap. At the
    prices I've been paying for screwmount lenses, that adds a high
    percentage to the total cost -- in one case, it would about triple the
    total cost.

    (I got the adapter back off of the lens by putting the locking tab
    back on the adapter, putting the lens on the camera, and finally
    removing the lens from the adapter.)

    So, what I'm wondering if is the M42 screw mount can be removed from
    the lens and replaced with a Pentax K mount from the same generation
    of Vivitar lenses (or the same generation of Kiron-made lenses,
    whichever would fit). If so, and if I could find such a lens which was
    unusable (damaged glass or whatever), maybe I could take the K mount
    from the dead, parts-donor lens and put it on mine, replacing the M42
    screw mount.


    Thanks,

    Greg
     
    Greg Lovern, Jan 5, 2004
    #11
  12. Yeah, I have a similar situation: a Vivitar 135 f:2.3 Series I in
    screw mount that I wouldn't mind having in K. As a stopgap, I picked
    up a Fuji ST701 with a nice, bright finder and an M42 mount, so the
    auto aperture works.
     
    Stephen H. Westin, Jan 5, 2004
    #12
  13. Greg Lovern

    Greg Lovern Guest

    Hi Stephen,

    That sounds like an interesting lens!

    Do you know how to determine whether a given potential donor lens'
    mount will fit on the old Vivitar?

    Also, do you know where I can find a list of inexpensive, but
    reliable, auto-aperature M42 bodies such as your Fuji ST701?

    Thanks,

    Greg
     
    Greg Lovern, Jan 6, 2004
    #13
  14. It is. Unfortunately, I have trouble focusing it on my K-mount Pentax
    P3, so the Fuji comes in handy. The original '70s Series 1's were
    designed in the U.S., but made in Japan.
    Not at all. Vivitar never made lenses; they source them from a variety
    of manufacturers, so it's anybody's guess as to whether another
    Vivitar lens was made in the same factory, much less have any common
    parts. I suppose getting another example of the same lens with the
    different mount would work, but would probably cost more than the
    original lens, unfortunately.
    http://www.toptown.com/nowhere/kypfer/fujica.htm

    or Google for "fujica slr" and similar. I had one ST701 with an
    intermittent wind mechanism, and my current one has a dead meater
    :(. I don't know how "reliable" they are compared to, say, Pentax,
    Ricoh, and the rest.

    <snip>
     
    Stephen H. Westin, Jan 7, 2004
    #14
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