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Thread: ULF film flatness idea

  1. #1

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    ULF film flatness idea

    About a week ago I took the "heart" out of a graphic arts camera at a print shop dating back to 1946 that is going out of business---the camera is, I think 1970's or 80's vintage, but I really don't know that for sure. I got a 20x24 bellows that's ~4 feet or ~1.2 meters long and the 45 cm f11 red dot altar lens. If I'd had a crew and a truck and a place to store it, I'd have gladly taken the whole camera. Looking darkroom side, there is a flip up and out of the way ground glass (plexiglas actually) and a flip up and into place vacuum requiring film holder that weighed enough to require a spring assist much stouter than a common household oven door.

    Some day I'd like to make this into a version of a field camera and if I made my own dry plates on plexiglas flatness wouldn't be an issue---though I'm not sure how UV transmits through plexiglas (perspex for the Brits and Aussies), for alt process printing I like. But, if I used film, keeping a piece of film that big flat from the edges has got to be problematic, right?

    Has anyone made holders that use vacuum assist using a small, battery-powered vacuum, through a hose to eliminate vibration, as a way to keep film flat in ULF holders? I don't think it would have to make the holders that much more enormous or heavy, but I'm often wrong about "obvious" things when it comes to engineering. I guess you'd have to be sure to clip the corners of your ground glass so you didn't implode the whole camera.

  2. #2
    Vaughn's Avatar
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    Re: ULF film flatness idea

    Someone in China is making them...

    \https://www.largeformatphotography.i...t-film-holders

    Whoops -- you have seen the post!
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

  3. #3
    Zebra
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    Re: ULF film flatness idea

    Quote Originally Posted by Fr. Mark View Post
    About a week ago I took the "heart" out of a graphic arts camera at a print shop dating back to 1946 that is going out of business---the camera is, I think 1970's or 80's vintage, but I really don't know that for sure. I got a 20x24 bellows that's ~4 feet or ~1.2 meters long and the 45 cm f11 red dot altar lens. If I'd had a crew and a truck and a place to store it, I'd have gladly taken the whole camera. Looking darkroom side, there is a flip up and out of the way ground glass (plexiglas actually) and a flip up and into place vacuum requiring film holder that weighed enough to require a spring assist much stouter than a common household oven door.

    Some day I'd like to make this into a version of a field camera and if I made my own dry plates on plexiglas flatness wouldn't be an issue---though I'm not sure how UV transmits through plexiglas (perspex for the Brits and Aussies), for alt process printing I like. But, if I used film, keeping a piece of film that big flat from the edges has got to be problematic, right?

    Has anyone made holders that use vacuum assist using a small, battery-powered vacuum, through a hose to eliminate vibration, as a way to keep film flat in ULF holders? I don't think it would have to make the holders that much more enormous or heavy, but I'm often wrong about "obvious" things when it comes to engineering. I guess you'd have to be sure to clip the corners of your ground glass so you didn't implode the whole camera.

    I've never pursued that with my 20 x 24 work. I just load them up and make the photograph. I've never noticed an issue with that approach. A more discerning eye may be able to prove a counter point to that with my photographs but overall I don't think its worth the time or money to worry about film flatness--but again that is for MY photography. Your mileage may of course vary depending on what you are wanting to achieve. Overall I don't worry about overcoming such things as dust, film flatness. I have too much on my hands overcoming me.

  4. #4
    Tin Can's Avatar
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    Re: ULF film flatness idea

    Good to know Monty, I am only going to 14X17" vertical with Medical holders and Ektascan.

    The simpler the better.

    Thank you!

    Quote Originally Posted by Monty McCutchen View Post
    I've never pursued that with my 20 x 24 work. I just load them up and make the photograph. I've never noticed an issue with that approach. A more discerning eye may be able to prove a counter point to that with my photographs but overall I don't think its worth the time or money to worry about film flatness--but again that is for MY photography. Your mileage may of course vary depending on what you are wanting to achieve. Overall I don't worry about overcoming such things as dust, film flatness. I have too much on my hands overcoming me.
    Images vastly preferred

    not game trying to


    focus


    In Time

  5. #5
    Vaughn's Avatar
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    Re: ULF film flatness idea

    1) Low tack adhesive spray (after removing the rails that normally keep the film in place)

    or

    2) Always point the camera up.
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

  6. #6

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    Re: ULF film flatness idea

    Vaughn,

    The low tack adhesive spray makes a lot more sense to me than always pointing the camera straight up!

    I have this tendency to go to the most complicated process I guess.

  7. #7
    Vaughn's Avatar
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    Re: ULF film flatness idea

    Nah, just a little back tilt will do...
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

  8. #8
    Drew Wiley
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    Re: ULF film flatness idea

    Vaughn - spray adhesive is damn dangerous stuff! Should never be used outside a spray booth and is highly flammable. A whole generation of the pro picture framing trade lost many members due to premature death, before word got around just how nasty that stuff is. I've already posted many times on how to make adhesive filmholders using the proper 3M sheet products. It's also easy to make a vacuum holder; and any little cordless vacuum does fine. Those silly little vacs even work for my 400 lb 30x40 inch vac easel in the lab, though I prefer a variable power small plug-in vac because one can only use rechargeable batteries so many times until they need replacement.
    Film sag is a serious issue even in 8x10 photography if one enlarges them much. I can't imagine doing ULF without some provision for improved flatness. And there's nothing quite as unnerving as seeing an ocean horizon line or allegedly vertical building squiggly-edged due to film flatness issues.

  9. #9
    Tin Can's Avatar
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    Re: ULF film flatness idea

    I suggest empirical testing with actual format and film you use, put into the holder, put holder in various real life shooting positions/angles, pull the DS and observe for week or more under your shooting conditions

    document with iPhone

    and post the dern evidence on this forum

    few will do that

    everything else is babble
    Images vastly preferred

    not game trying to


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  10. #10
    Drew Wiley
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    Re: ULF film flatness idea

    That "dern evidence" has been well known for generations. It's been an obvious problem ever since flat glass or metal plates were no longer used. Later a little tab of ATG tape was put behind the middle of the film - not the best idea but it halfway worked. Vac holders in one fashion or another are nothing new. And if you want serious evidence, find me a graphics copy camera anywhere that didn't require a vac easel - the real ULF machines!
    The bigger the film, the more the overall problem. Sinar offered adhesive holders in 5x7 and 8x10; and I think that right around 5x7 it starts becoming a noticeable issue with moderate enlargements. For technical or scientific projects, even 4x5 should be controlled. For ordinary contact printing applications, all depends. ULF film is generally contact printed, but mere perceived sharpness is not all that is in play here. I once saw a 16X20 AA print with a distinct sag in the ocean horizon.

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