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Schneider Kreuznach Scope Lens Adjustment?

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  • Schneider Kreuznach Scope Lens Adjustment?

    I think the astigmatism adjustment on one of the scope lenses at one of the screening
    rooms I work at needs a bit of a touch-up. I forgot to take a picture before I left last nite,
    but the lens in question is a Schneider Kreuznach very similar to the one in this photo
    I found online. I've never adjusted one of the Schneider lenses, and I'm just curious
    how to do the adjustment.
    > I KNOW how to do an astig adjust optically <- - What I'm
    asking is which of the mystery screws on the lens need to be loosened to be able
    to adjust the lens
    . Is it just those two screws on the front that say "Lock"? Do they
    come out or just get loosened? Do those 4 screws on the side have anything to do
    with it, or do I leave those alone?


    I forgot to takapicture last nite of the lens I'm working with, but
    here's a montage I made from photos I found online of a similar lens

    ScopeLnsAdjust.jpg

    Fortunately, I have one of the actual old SMPTE scope lens adjusting loops,
    as well as a roll of good crosshatch/grid film shot as part of a camera test
    I can use while making the adjustments.

    THANKS!
    . . . . now, if only I could figure out how to pronounce "Kreuznach"
    Last edited by Jim Cassedy; 05-25-2022, 01:05 PM.

  • #2
    As you mentioned, you're familiar with Scope attachment adjustments.
    This is straight forward on these. There are 2 screws, one is a locking screw, that you have to loosen, the other one is the adjustment screw, that is to be turned until best image.
    Nothing difficult.
    The difference betwen the 2 types is, the older one has the little thumb screws, the newer one requires an 0.1" Allen wrench to do the adjustment (cheaper in mfg).
    Good luck.

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    • #3
      Originally posted by Jim Cassedy View Post
      [B]
      . . . . now, if only I could figure out how to pronounce "Kreuznach"
      "Kroitz-Nock"

      Bonus points if you can produce a tiny bit of phlegm in the back of your throat on the last syllable.

      My ex-wife's name is Kuebel... Pronounced "Kee-ble."

      I think that there's an "'I' before 'E'" rule that tells you which of a double-vowel takes precedence but I forget how it goes.

      Comment


      • #4
        My rule-of-thumb is with German words: there are no silent letters. Z and S pronounce oppositely. It isn't so much the I before E as you are "landing" on that last vowel so it has that long sound and you sort of slid through the first one so an "ie" in a word will sound pretty much like just the "e." And "ei" will sound mostly like the "i" but, say, the German word for egg is Ei and pronounces, in English, as "eye" but the "E" was in there and you just glanced through it on your way to the "i." I self-tought on German and very poor with it, with a decided cinema emphasis as I worked with Kinoton equipment for most of my 4+ decades. I mean, you need to work with Schaltplan (schematic/circuit diagram) and know what a Bildklappe (changeover dowser) is. Note, the "e" on the end of the word is NOT silent.

        So, back to Schneider lenses.

        On the compact integrated anamorphic...the original one had the knobs on the end and little wings (Jim's right hand picture) and the later one, the "ES" eliminated the wings and made the adjustments hex (allen) keys. Just the adjustments on the face are used...NEVER anything on the side. If you think about it, when using a compact anamorphic, there is a large percentage that will obstruct anything along the barrel of the lens.

        How to adjust? Like any anamorphic, you want to focus the two planes independently and the best way is to defocus the anamorphic by, say moving the distance to either extreme and one that is furthest away from your actual throw. So, say infinity. Put your target up with lots of horizontal and vertical lines. Adjust your main focus (or set your lens position relative to the film) such that the horizontal lines are clear (and the lens is in proper rotation). Once the horizontal lines are sharp and horizontal, THEN adjust the anamorphic's distance/focus/astigmatism to bring the vertical lines into focus too. With good anamorphics, you shouldn't need to go back in forth but be prepared to do so anyway.

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