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  1. #11
    Kevin Kehler's Avatar
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    Quote Originally Posted by BetterSense View Post
    My favorite LF macro lens is from an RB67. It easily covers 4x5 at most 'indoor' ranges, covers with movements at macro ranges, and stops down farther than most LF lenses.

    A lens for 35mm is probably pushing it, though.
    How did you go about mounting that? I am assuming that you are not firing the leaf shutter but rather doing a "hat over the lens" type of exposure control. I have a couple of RB/RZ lens and would like to do more macro with my 5x7.
    Once a photographer is convinced that the camera can lie and that, strictly speaking, the vast majority of photographs are "camera lies," inasmuch as they tell only part of a story or tell it in a distorted form, half the battle is won. Once he has conceded that photography is not a "naturalistic" medium of rendition and that striving for "naturalism" in a photograph is futile, he can turn his attention to using a camera to make more effective pictures.

    Andreas Feininger

  2. #12

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    Quote Originally Posted by E. von Hoegh View Post
    You do need to reverse it if you want a reasonably flat field.
    Correct rule of thumb, incorrect reason. The right reason is that lenses designed for general use are optimized for a large subject in front of the lens and a small image behind it. These lenses should be reversed when used at magnifications greater than 1:1 (small subject in front, large image behind) to preserve their optimizations.

  3. #13

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    Kevin, PMFJI.

    A while ago I got a lens made for a Koni-Omega to use on a 2x3 Graphic. Same problem as you asked about, the shutter is made to be cocked and fired by the camera body. I unscrewed my lens' cells and put them in the right size Copal shutter. #0, as it happens, and I had its aperture scaled for the lens. The 140 RB macro lens is, I think, in a #1.

    You should be able to do the same with an RB lens. Coverage on 5x7 (210 mm circle) will be a little iffy below a little over 1:1.

    I understand your desire to use what you have, but you might be better off with, e.g., a 150 Apo-Ronar (in #0 or front-mounted on an ex-Polaroid MP-4 #1 Press) or G-Claron (cells are direct fit in a #0), both for cost and for usable range of magnifications.

    Good luck, have fun,

    Dan

  4. #14

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    Quote Originally Posted by Dan Fromm View Post
    Correct rule of thumb, incorrect reason. The right reason is that lenses designed for general use are optimized for a large subject in front of the lens and a small image behind it. These lenses should be reversed when used at magnifications greater than 1:1 (small subject in front, large image behind) to preserve their optimizations.
    And my understanding is with asymmetrical lenses those optimisations include field flatness/spherical aberration. Is this incorrect?

  5. #15

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    Quote Originally Posted by E. von Hoegh View Post
    And my understanding is with asymmetrical lenses those optimisations include field flatness/spherical aberration. Is this incorrect?
    This true for most of the lenses we use but incomplete. There are other aberrations.

  6. #16
    EKDobbs's Avatar
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    Thanks for the responses. I knew it wouldn't be optimal, I was just curious if you could stop it down to f/22 (which slightly increases image circle IIRC) and move it away from the film plane to maybe cover a 5x7.

    I understand now that it's probably very unlikely. Still, I could make tiny little 2x2 inch paper negs.
    In other worlds he has
    darker days, blacker swells.
    Strokes that mix noir revenge
    on waves of grey.

  7. #17

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    If you move the lens far enough from the film plane, it will cover any format you might want to use. But you will then be working very close up. You do understand how focusing works, don't you?

  8. #18
    BetterSense's Avatar
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    Exactly. The lens-to-film distance of most 35mm lenses is like 25mm or something. So if your subject is 25mm away, just flip the lens over, and I see no reason why a 35mm lens wouldn't cover 4x5. Usually you want more than 25mm from your subject, though, for lighting reasons.
    f/22 and be there.

  9. #19
    EKDobbs's Avatar
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    Quote Originally Posted by Dan Fromm View Post
    If you move the lens far enough from the film plane, it will cover any format you might want to use. But you will then be working very close up. You do understand how focusing works, don't you?
    Yes I do, thanks. I just like to hear from people who may have actually tried it in person, because sometimes there are problems that the simple rules don't predict. Or maybe someone has a solution for me that I didn't think of. Either way, I'm well aware of how a camera focusses, but I appreciate your concern.
    In other worlds he has
    darker days, blacker swells.
    Strokes that mix noir revenge
    on waves of grey.

  10. #20

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    Quote Originally Posted by BetterSense View Post
    Exactly. The lens-to-film distance of most 35mm lenses is like 25mm or something. So if your subject is 25mm away, just flip the lens over, and I see no reason why a 35mm lens wouldn't cover 4x5. Usually you want more than 25mm from your subject, though, for lighting reasons.
    Look up 35 mm SLRs' flange-to-film distances, also called registers. When using a lens made for a 35 mm SLR reversed as a macro lens, the minimum "back of lens" to subject distance is the register. The OP has a 44/3.5 lens extracted from a Kodak Signet. It isn't for an SLR and the Signet's register isn't published, but since it is a tessar type its minimum back of lens to subject distance will be around 40 mm.

    I've known the joy of trying things out, also the joy of finding good uses for what appears, at first glance, to be scrap so I don't want to discourage the OP from trying to find a use for his ex-Signet 44/3.5. That said, all the lens is good for on 4x5 or 5x7 is relatively high magnification macro work.

    If I were in the OP's situation and wanted to shoot macro on 4x5 or 5x7 I wouldn't start with a 44 mm lens or, for that matter, any of the 35 mm SLR more-or-less normal lenses I have. This because a lens that short will cover the formats only at relatively high magnification. Shooting LF at relatively high magnification is possible, has been done, is very difficult. Shooting at magnifications from 1:8 to 2:1 is hard too, but much easier than shooting above 2:1 or so.

    If I wanted to do that, I'd look for a decent process lens, focal length around 210 mm, for shooting up to perhaps 1:2 on 5x7 and for a decent process lens, focal length around 150 mm, for shooting above 1:2 on 5x7 and from 1:8 up on 4x5. First choice for a 150 would be a 150/9 G-Claron even though the one 150/9 G-Claron I've had was noticeably worse than the 150/9 Apo Ronars I still have.

    An alternative would be a decent enlarging lens whose cells fit a standard shutter. I'm a little partial to 105/4.5 and 150/5.6 Comparons as low-budget macro lenses because they fit #0 shutters so are easily reversed.

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