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  1. #1
    JG Motamedi's Avatar
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    Ron Wisner on ULF portrait lenses

    Today, breezing through View Camera I read an article by Ron Wisner on ultra-large format lenses. He made a very interesting point, which I will try to recount.

    A head and shoulders portrait on ULF is close to 1:1. Therefore, the effective focal length is significantly increased. Example; if I shoot a portrait at 1:1 using 11x14 with a wide angle 240mm lens, the lens--in affect--becomes a "normal" 480mm lens because I am shooting at 1:1. Does this make sense? Can I shoot a 300mm lens for 1:1 portraits and expect it to act and look like a 600mm lens at infinity? I understand how this works with "bellows factor", but I still can't see how they would look the same...

  2. #2
    Dave Wooten's Avatar
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    no,

    Your 300 focuses at infinity at 300 mm and covers say 8
    x 10. Pull beyond your 300 and you have focused closer than infinity, and your film coverage increases, therefore your lens might cover say 16 x 20 in close focus (portrait distance) your depth of field of course does not go to infinity.


    ULF photographers wanting to do landscape at infinity must use a lens which will cover the film at the designed focal length for infinity..


    ULF portrait photographers do not necessarily need a lens that will cover their film at infinity.

    For still life, fine art, portrait, etc a lot of "common" readily available and inexpensive lenses will cover 20 x 24. I think that was Ron's point.

    Try for example one of your 90mm 4 x 5 lenses on your 8 x 10 or 5 x 7 and pull the bellows and move the camera until you have a wall for example in sharp focus...it will cover the format......with smaller depth of field of course.

  3. #3
    JG Motamedi's Avatar
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    I am don't think Ron (or I) were writing about coverage, but rather about effective focal length and bellows extension. Shooting at 1:1 we must open up two stops because of "bellows factor" or "extension factor"--the reason we must do so is that at different enlargement ratios, the FL of lenses varies. Consequently, shooting at 1:1 a 150mm lens effectively becomes a 300mm, but the engraved aperture scale is for a 150mm lens. So, according to Ron, if we are shooting 1:1 portraits (or anything) we can use lenses much shorter than normal, and still get the same results. One can not do this with "lesser format" portraiture because the enlargement ratios are much smaller. An head and shoulders on 11x14 might be 1:1, while on 4x5 it might be 1:3.

  4. #4
    Dave Wooten's Avatar
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    additional thought: Your 600 mm lens focused on the same subject for portrait would have greated lens to subject distance of course that the 300 mm...If you focused your 600 at infinity you portrait subject of course would be out of focus at that near distance.

    Also I am sure you know ... if you were to use the 300 for 1:1 or whatever say you did pull the bellows to 600 mmm, the focal length is then 600 mm even though you are not focused at infinity.....If your light meter says f/8 it assumes you are shooting a lens at its designed focal length for infinity,

    the size of the f stop for f /8 for 300 is of course 300/8

    the size of the f stop for f /8 for 600 is 600/8.....so just open up accordingly or add exposure etc.

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    Dave Wooten's Avatar
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    Ok JG I see what you are saying, I might have gotten off track a bit there

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    clay's Avatar
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    Yeah, the weird thing is that if you go through the calculations, the depth of field at the same enlargement ratio would be the same with the two focal lengths. So you really can't win in the DOF department.

  7. #7
    David A. Goldfarb's Avatar
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    Yes, in the macro range--closer than about 1:10--DOF is essentially the same for the same magnification factor, no matter what the focal length, and portraits larger than 8x10" are generally in the macro range.

    Wisner's article makes a lot of intuitive sense to me. As I go up in format, I'm usually using shorter and shorter lenses for portraits.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
    Photography (not as up to date as the flickr site)--http://www.davidagoldfarb.com/photo
    Academic (Slavic and Comparative Literature)--http://www.davidagoldfarb.com

  8. #8
    bobfowler's Avatar
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    Quote Originally Posted by David A. Goldfarb
    Wisner's article makes a lot of intuitive sense to me. As I go up in format, I'm usually using shorter and shorter lenses for portraits.
    Very much so. I find a 10" lens is perfect for 4X5 H&S, a 12" is great for 5X7, and 14" to 16" is plenty for 8X10.
    Bob Fowler
    fowler@verizon.net
    Some people are like Slinkies. They're really good for nothing, but they still bring a smile to your face when you push them down a flight of stairs.

  9. #9

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    Jason

    I did a half day session with a photographer who specialised in 11x14 platinum portraits at the mammoth camera workshop a few years back. He had a range of samples with him and most were head and shoulders. His standard lens was a Fuji 450 12.5 and he also used a Fuji 600 but rarely. Most of the portraits were close to 1:1 using around 700-800mm of bellows. DOF was very small and I had a lot of trouble focussing this setup although he could do it easily.

    Platinum portraits this size are something to see, the 3D quality was like nothing else I've ever seen.

    The "look" you get with the lens is relative to where you place the camera and not the focal length.

    Clayton

  10. #10
    Dave Wooten's Avatar
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    Clayton,

    That wouldn't have happened to have been Adrian Engle would it?

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