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  1. #11

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    Everything is relative, right?

    Instead of thinking about a tilted lens, think of it in terms of a tilted film plane.
    And take it to extremes: tilt the film plane 90 degrees.
    Then you'll notice that the side it presents to the cone of light coming from the lens is as small as the film plane is thick.
    So the image circle doesn't grow when you tilt a lens, but the film format, as seen from the lens, actually shrinks.

    So no coverage problems with tilts.
    Tilts do not require a larger image circle (which is why, for instance, the regular Zeiss/Hasselblad lenses work perfectly well on the FlexBody - if only people wouldn't think it is a shift camera, which it is not). On the contrary: coverage could be less, the image circle smaler, and still cover the full format.

    When you tilt the lens, the image circle shifts. Shift is then needed to put the film plane back inside the image circle.
    But the image circle does not need to be bigger.

  2. #12
    2F/2F's Avatar
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    Quote Originally Posted by Steve Smith View Post
    They will all require a larger image circle diameter. Think of it in 2D terms viewed from the side of the camera and draw a triangle from the top of the film to the centre of the lens, down to the bottom of the film then joining up back at the top of the film. The triangle represents a hypothetical image coverage of the lens.

    Now tilt the lens. The triangle will also tilt. The triangle you have drawn or imagined will now not cover the whole of the film as it was only big enough to cover the exact film height.

    Now do the same excercise but with a triangle with points a bit higher and lower than the top and bottom of the film and you will see that it is now possible to tilt the lens and the coverage triangle and still cover the film.


    Steve.
    The Super 23 only has rear tilts; it has no other movements. The film plane tilts within a fixed image "cone" with this camera.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

    - Rob Tyner (1944 - 1991)

  3. #13
    Steve Smith's Avatar
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    Quote Originally Posted by 2F/2F View Post
    The Super 23 only has rear tilts; it has no other movements. The film plane tilts within a fixed image "cone" with this camera.
    Then ignore everything I wrote!!!


    Steve.
    "People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.

  4. #14
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    Hello again, funny the thread is still going strong. My solution will probably be that I will buy a press 23 setup (a body a few lenses and some backs) and then later ad a universal body with polaback. Negative film is still my highest priority (yes, I'm aware that you can get negs from fujiroids as well).

    Anybody wanna help fund this buy by buying a Lynx 14E IC?

    And thanks 2F/2F, but the graphics are way to cumbersome for my usage. I just really need three lenses, a wide, a normal and a shortish tele.

  5. #15
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    Turns out the the earlier version of the 100 3.5 with the chrome shutter will not cover the polaroid format.

    The black shuttered 100 3.5 was an upgraded optical design and according to 2F it does cover.

  6. #16
    NJS
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    my friend adapted few Mamiya Press for various lenses, although it might seems offtopic, I thought I might add some interesting stuff here he did:
    http://www.flickr.com/photos/branavo...7624577189079/

  7. #17
    2F/2F's Avatar
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    My 100 mm f/3.5 that covers with no vignetting is a silver shutter version.
    2F/2F

    "Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."

    - Rob Tyner (1944 - 1991)

  8. #18
    brucemuir's Avatar
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    ^ I'm not doubting you
    but all other evidence seems to point to different results than you've been getting

    the camerapedia states


    "Lens System
    The lens system incorporates a breechlock mount unique to the Mamiya Press, and each lens is mounted in a Seikosha leaf shutter. Lenses of fixed focal lengths from 50mm to 250mm were produced, all of which covered up to 2x3 film sheets, while the 127mm and 75mm lenses offered greater coverage necessary for the 2 7/8 x 3 3/4 inch images produced by the Polaroid backs. "

    although camerapedia may not be the definitive authority.

    Then if you go to this guys page
    http://moominsean.blogspot.com/2010/...oid-600se.html
    and scroll down halfway he states:

    "Anyway, on to the Universal. The most obvious advantage the Universal has over the 600SE is the lens selection. This comes with a caveat, though...most of these lenses were designed for 120 film. The area of Polaroid film is larger than the largest 120 back available (6x9). This means that some of these lenses have falloff beyond the normal area for 120. That's vignette to you and me. Now I, personally, don't take this as a negative. But, depending in the lens, it's kind of like having an expensive, super-sharp toy camera! Here is an illustration of the different exposure sizes with the 100mm lens for the Mamiya Universal."

    and shows example jpgs of polaroids with corner falloff/vignette with a 100mm 3.5

    I don't own a Polaroid holder and the vignette wouldn't be a deal killer for me anyway but I'd like to know if sharp corners are possible.

  9. #19
    brucemuir's Avatar
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    Here's another example on flikr that clearly shows vignette with the 100mm 3.5
    http://www.flickr.com/photos/6261/4108495035/

  10. #20
    xya
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    I have 3 100mm 3.5 lenses, 2 silver and one black. no vignetting for all 3 of them.

    [I also own a polariod 600se with all 3 lenses (75mm, 127mm and 150mm). the 600se lenses are fine of course, the cover the whole format.]

    for the different mamiyas I own I have a 65mm which shows quite some vignetting with the polaroid back. my 127mm with mamiya lens mount is fine, as expected. the 75mm and the newer 150mm should be covering the whole format as well.

    how about the 50mm, the 100mm 2.8, the older 150mm and the two 250mm lenses? has anybody tried them on a polaroid back?

    I would like to have some more information before I try to buy one theses lenses. thanks in advance.

    reinhard

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