Focus Problems

Discussion in 'Large Format Cameras and Accessories' started by Lobalobo, Dec 18, 2008.

  1. Lobalobo

    Lobalobo Member

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    After a couple of years shooting, developing, and contact printing b&w 4x5 film on a pinhole camera, I decided to expand my horizons and shoot 4x5 with a lens, using an old Crown Graphic and Fujinon 135mm. When I had my first roll of Provia developed in a local shop, I asked the owner whether he sold small light tables/boxes. He laughed and said no that digital has eliminated the market for such a thing, saying that he couldn't remember processing 4x5 before my shots. I responded that I'd be shooting digital too, if it didn't cost $20,000 to replicate the quality of my $350 Crown Graphic setup and $300 scanner (that doubles as a means to copy work documents).

    But I lied. I aspire to having my $650 setup match a $20,000 digital back, but in one respect it never will because a digital camera (even a point-and-shoot) will focus, accurately and fast. In a prior post I idiotically thought of every reason that I was not getting sharp focus on images that looked sharp on the glass except the right one--slow film, thus long exposure, and an unstable tripod. (You think this would have occurred to me as nothing was in focus, at any depth.) This time, with Provia I just took to the shop, I shot at shorter exposure and on more stable ground. My primary test shot was of my daughter wearing a puffy winter coat. I got a crystal clear, razor sharp, full texture detail image, of the front of her coat. Her face, where I attempted to focus about ten seconds earlier, was fuzzy. As it turns out, my daughter wasn't so interested in being a statue while I closed down the lens, set the shutter, and pulled the slide. She shifted her weight back, shuffled her feet maybe, and with the f-stop needed for a fast shutter on 4x5 film, even in daylight (though not bright sun), that's all it took.

    There are, of course, some obvious solutions. Put the kid on a stool, use faster film, produce or wait for brighter light, etc. I wonder, though, whether are other tricks that I might be missing to minimize the time between focus and shutter release (a solution that costs less than $20,000). Can't imagine what, but thought I'd ask.
     
  2. kameranerd.com

    kameranerd.com Member

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    My Crown Grapic has a rangefinder, it work fast.
     
  3. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Yup. A calibrated rangefinder will let you check focus after inserting the filmholder and pulling the darkslide.

    Another method is to use a string to measure the focus distance. Put a knot at the end of the string, and tie the other end to something stable like the tripod, and have the subject hold the string, say to her nose, while you focus on the eyes. Then you can use the string again to check the focus distance after you've pulled the darkslide. I do this at wide apertures with an 8x10" camera, and focus is dead on every time.
     
  4. Lobalobo

    Lobalobo Member

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    Aug 26, 2006
    Shooter:
    4x5 Format
    Thanks to both of you. (And from my original post, I noted mistakes both in describing 4x5 as being in a "roll"--would be nice,right--and in neglecting the time it takes to put the film holder into the camera, which also risks shifting the tripod; but you both got the point, so thanks.) As for a rangefinder, my Crown Graphic didn't come with one; I know that would help but is it really accurate enough, even if calibrated? The string is a great idea. I'll try it. (See there was a trick I hadn't thought of.) Thanks again.
     
  5. fschifano

    fschifano Member

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    Once calibrated, the rangefinders on Crown and Speed Graphics are very accurate, no question about it. The side mounted Kalart rangefinders are the best if you change lenses, since you can adjust them for any focal length within its design parameters. The top mounted rangefinders have interchangeable cams paired with each lens.