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  1. #11
    David A. Goldfarb's Avatar
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    Focus stacking is a great technique, but it's off topic for APUG, so the question for this forum is, how to do what you want using traditional techniques.

    Camera movements are a plus, if the subject lends itself to it. At very high magnification (say more than about 6x comparing the size of the object to the size of the image on film), DOF is going to be razor thin, so it's all about using the DOF you have most effectively. Diffraction does become an issue at higher magnifications, because the effective aperture is in fact much smaller than the aperture as set on the lens, so you may choose a wider aperture to get the sharp part of the image sharper, even if it costs you some DOF.

    There are other problems when you go up in format--mainly you need more light. If you are using artificial light, then put the light as close as possible to the subject--really close, presuming the heat from your light source won't destroy the subject--to get as much out of the light you have. You need a really solid tripod, head, and ideally a macro focusing rail unless you are using a view camera with focus on the rear standard, and you may want to do things like sandbag the camera and add weight to the tripod. You may need to be concerned about the solidity of your floor. This is true whether you are using strobes or continuous lighting, because even with powerful studio strobes, you will likely need multiple pops to get enough light for the exposure.
    flickr--http://www.flickr.com/photos/davidagoldfarb/
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  2. #12

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    Quote Originally Posted by David A. Goldfarb View Post
    Focus stacking is a great technique, but it's off topic for APUG, so the question for this forum is, how to do what you want using traditional techniques.
    I am sorry. I did not realize shooting a series of film stacks, scanning them, and then stacking them is off topic.

  3. #13
    BetterSense's Avatar
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    There are other problems when you go up in format
    At least I understand all those problems. I don't fully understand the effect of camera format on the final print's DOF and sharpness. I still don't understand the merits of shooting to a smaller format and enlarger more, versus shooting to a larger format and enlarging less.
    f/22 and be there.

  4. #14

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    Quote Originally Posted by BetterSense View Post
    At least I understand all those problems. I don't fully understand the effect of camera format on the final print's DOF and sharpness. I still don't understand the merits of shooting to a smaller format and enlarger more, versus shooting to a larger format and enlarging less.
    If you are looking at equal DoF and equal relative image size (unequal f-numbers and unequal magnification), then there is no advantage to format in macro photography (1x or greater). The only advantage is in granularity and resolving power of the film on appearance.

  5. #15
    BetterSense's Avatar
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    Sorry I don't understand. I'm trying to decide the advantages between 35mm and 4x5.

    If you are looking at equal DoF
    I am looking at equal DOF between the two formats...I want to have my entire subject sharp, if possible.

    and equal relative image size
    The final prints between the two formats will be the same.

    then there is no advantage to format in macro photography (1x or greater)
    Ok, that's what I thought but I'm still not so sure.

    Consider 3 scenarios:

    Consider my little seed pod I'm photographing; it's about golf-ball-size and roughly spherical.

    1. Say I'm using a 4x5 camera and I set it up 1:1 so the image of the seed pod is 1-inch (life-size) on the 4x5 film. I adjust my aperture to get 1/4 inch of DOF. Then when I print I enlarge the negative until seed pod to 10-inches wide on the print, and crop the print to 11x14.

    2. Say I'm using a 4x5 camera and I set it up 4x magnification so that the seed pod is 4 inches wide on the film. I adjust my aperture until the DOF is 1/4 inch, same as before. Then I enlarge the negative until the seed pod is 10-inches wide on the print, and crop the print to 11x14.

    3. Say I'm using a 35mm camera and I set it up .25x magnification so that the seed pod is 1/4 inches on the negative. I adjust the aperture until the DOF is 1/4 inches. Then I enlarge the negative until it's 10-inches wide on the print, and crop the print to 11x14.

    What differences in results can I expect? Theory predicts that I will have to use the smallest aperture for scenario 2, correct? Ignoring things like film grain, reciprocity and light issues, what differences can I expect the prints to have?
    f/22 and be there.

  6. #16

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    No difference. Since we are talking about macrophotography and you are equalizing the object space, the image space printed at the same scale should turn out the same.

    Yes, scenario 2 gives you the smallest effective aperture (f-number). But all three scenarios will have the same numeric aperture.

  7. #17
    keithwms's Avatar
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    No format is any better than another for macro. What matters is which gear best enables you to see what you want and consistently delivers the goods without too much fuss.

    My preferred macro system is the mamiya rb67. It is very stable, uses leaf-shuttered lenses, and features bellows focusing... all helpful for macro. If I need tilts or back focus, I will sometimes put an rb lens (or the fast rz 110/2.8!) or Nikkor 120 AMED lens on a rittreck 5x7, that is a nice, stable platform. Sometimes you really do need tilts, if you are fighting for every last micron of DOF. That plus other rear movements and back focus can be very helpful.

    Another macro system that I enjoy is the mamiya 645 pro with the 80/4 macro lens, that is good fun. I like the lens so much that I sometimes use it on 35mm as well.
    "Only dead fish follow the stream"

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  8. #18
    David A. Goldfarb's Avatar
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    Quote Originally Posted by Hikari
    Quote Originally Posted by David A. Goldfarb View Post
    Focus stacking is a great technique, but it's off topic for APUG, so the question for this forum is, how to do what you want using traditional techniques.
    I am sorry. I did not realize shooting a series of film stacks, scanning them, and then stacking them is off topic.
    Indeed, hybrid digital/analogue topics are off topic for APUG, but are completely appropriate on our sister site, http://hybridphoto.com
    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

  9. #19
    BetterSense's Avatar
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    Yes, scenario 2 gives you the smallest effective aperture (f-number). But all three scenarios will have the same numeric aperture.
    I thought that numeric aperture was just another way to express the same quantity that is expressed with f-number. How can the numeric aperture be the same in all three scenarios when there are 3 different in-camera magnifications, all with the same DOF?
    f/22 and be there.

  10. #20

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    Quote Originally Posted by BetterSense View Post
    I thought that numeric aperture was just another way to express the same quantity that is expressed with f-number. How can the numeric aperture be the same in all three scenarios when there are 3 different in-camera magnifications, all with the same DOF?
    Numerical aperture (NA [sorry, my mistake]) is the angular size of the entrance pupil from the object plane. It is an object space factor. f-number exists in the image space.

    f-number can be thought of two ways: the focal length divided by the entrance pupil or the angular size of the exit pupil from the image plane. An f/5.6 aperture presents the same angular light cone to the image plane regardless of the focal length. This is why depth of focus (the tolerance at the film plane) is only dependent on the f-number.

    Likewise in the object space where the sample is, depth of field is dependent on the numerical aperture. Just like the f-number, the angular size of the entrance pupil is dependent on the dimension of the aperture and the distance to the object plane. You will find that each one of your scenarios having the same DoF will have the same numerical aperture.

    Numerical aperture also is related to the resolving power at the object plane, just as the f-number is related to the resolving power at the image plane.

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