Mamiya RB67 Polaroid back only get square images

Discussion in 'Medium Format Cameras and Accessories' started by j-dogg, Jul 25, 2014.

  1. j-dogg

    j-dogg Subscriber

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    Have what I believe to be a Mamiya back, when using FP100c I only get the center square part exposed, is that normal?
     
  2. aRolleiBrujo

    aRolleiBrujo Member

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    yes

    I assume so, because the Polaroid is its own entity and not 6X7. Congratulations the the Polaroid back, I loved my own!
     
  3. aRolleiBrujo

    aRolleiBrujo Member

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    someone somewhere had explained the technical aspect of it all to me awhile back, however, I forgot it, though, if you see this image, you will notice that it is sort of partially covered, though, i forget why. its about the 6X7 and the Polaroids square opening or something like that?!
    [​IMG]Untitled by a.rodriguezpix, on Flickr
     
  4. aRolleiBrujo

    aRolleiBrujo Member

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  5. aRolleiBrujo

    aRolleiBrujo Member

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  6. j-dogg

    j-dogg Subscriber

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    So there is pretty much no way to get full coverage on FP100c with an RB67?
     
  7. aRolleiBrujo

    aRolleiBrujo Member

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    Well, In a sense, that is the full coverage, since the formats are completely day and night! One being the 6X7 sensor of the RB67 and the other being the Polaroid back and its size limits. FUJIFILM FP-100C 3.25 X 4.25 Inches.
     
  8. j-dogg

    j-dogg Subscriber

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    well....crap

    time to find a Polaroid 250 I guess.
     
  9. aRolleiBrujo

    aRolleiBrujo Member

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    Or 4x5 and/or 8X10! i'd love the 8x10!
     
  10. shutterfinger

    shutterfinger Subscriber

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    1 inch=2.54 cm=25.4mm
    6cm/2.54=2.36 inch
    7cm/2.54=2.76 inch
    3.25-2.36= .89 inch/2=.445
    4.25-2.76= 1.49 inch/2=.745

    If your film holder has a 6cm x 7cm film gate and it aligns perfectly with the camera then you should get an image with a border 1.13cm x 1.89cm on each side.

    The film gate of the holder will limit the image size if it is smaller than the cameras image gate opening; the cameras image gate opening will limit the image size if it is smaller than the film holder film gate. Positioning of the film holder film gate with respect to the camera image gate opening will determine the border positioning.
     
  11. mdarnton

    mdarnton Member

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    You don't get 4x5 images on your film by putting 4x5 film in your 35mm camera, do you? Why would you expect different with Polaroid film? The RB67 takes 6x7 cm pix. About the most you can expect, because the rotating back needs a square hole in the camera to turn both ways, vertical and horizonta, is a 7cm square picture, regardless of what film you use. You might get a hair more, but I wouldn't count on it, and less if one dimension of the film is less.
     
  12. analoguey

    analoguey Member

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    A 'Mamiya' modified Polaroid or Mamiya-Press back will get you a 7x7 image with black border on its sides, apart from the white Polaroid border.
    A 'Lane' Polaroid back gets you the image on one side with an ugly black rectangle next to it. (and is more plasticky-flimsy too)

    Sent from Tap-a-talk
     
  13. Xmas

    Xmas Member

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    More simply the RB67 is 7x7 camera the 120 and 220 backs cut the image to 67 or 76...
     
  14. itsdoable

    itsdoable Member

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    You have full coverage, it's 7x7 (or a little bit larger than 7x7). Your 120 film backs crop the camera's coverage down to 6x7.
     
  15. vdonovan

    vdonovan Subscriber

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    Charming to refer to the "sensor" in an RB67.
     
  16. aRolleiBrujo

    aRolleiBrujo Member

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    It is an honest rookie mistake, however,whether I knew the technicalities or not, I still shot it. xD