Help with learning swings and tilts? Interiors w/ 5x7

Discussion in 'Large Format' started by keithostertag, Jun 9, 2005.

  1. I need some basic advice about how one uses swings and tilts in a
    practical sense.

    I have an ancient Ansco 5x7 wooden field camera which I sometimes use
    for doing environmental portraiture in people's homes. In the past
    when I have wanted to point the camera down for a shot I would tilt
    both the front and rear standard back to vertical to correct both
    convergence and focus. Is this fairly acceptable practice? It seems to
    have worked for me in the past.

    But the other day I thought I'd test a rear swing in order to correct
    the shape of a mirror on the wall. My camera does not have a front
    swing. After processing the film I was surprised to see how
    out-of-focus the entire right side of the image is. I probably could
    have seen this if I had looked carefully on the ground glass image,
    but the lighting was pretty dim. I'm thinking I need a brighter GG.

    Hmm... I am guessing that in normal practice one would have swung the
    front standard to be about parallel to the rear standard to correct
    the field of focus? Is that right?

    Then I thought... why did they make cameras with a rear swing but
    without a front swing if this is what happens? I must be missing
    something here... In what case would you use rear swing that would not
    cause this kind of change in focus? I thought I had always read that
    the rear standard movements changed perspective but did not affect
    focus, ... so I am confused.

    It doesn't look to me like I ran out of image circle- I am using a
    Calter 90mm f4.5 lens mounted on a recessed lens board. Shot at f22,
    exposed for 10 secs, developed in HC110 dil G for 6 minutes (about N-4).

    I realize there are much better cameras to do this sort of work with,
    but this is what I have for now. I just thought someone might help
    explain to me what's actually happening here and how to improve my
    technique with the equipment I have.

    Thanks,
    Keith
     
  2. Here's the right side of the image so you can beter see the problem.
     
  3. Swing and tilt movements ofthe rear standard modify both perspective rendition AND
    focus distribution. Swing and tilt movements of the front standard only affect focus
    distribution.

    And sometimes ometimes you just have to stop down more.
     
  4. If you point the camera down, and tilt both front and rear standards back to the vertical, that is exactly equivalent to shifting the front standard down or the rear standard up. It selects a lower part of the scene within the frame. You should think about the relative positions of the standards to one another and their relation to the vertical. It doesn't matter how you obtain the relative positions, it is just the final result that counts. Try to imagine the standards as free standing planes which you could in principle position anywhere you want. If the standards are parallel and both vertical, you will select the lower part of the scene if the front standard is centered below the rear standard, however that was achieved.

    Pointing the camera up or down and tilting the standards back to vertical is a standard method to achieve a rise or fall in cameras which don't alow direct moements up or down of the standards.

    Similar remarks would apply to swings and shifts right or left. But if your camera doesn't allow you to swing the front, then clearly you can't do it that way.

    The purpose of a swing which results in the standards not being parallel is to change the plane of focus. If you don't understand such matters you should read up on Scheimpfulg's Rule. Again it doesn't matter whether you swing the front or rear standard, provided you can compensate by turning the camera and perhaps using a sideways shift. But if sideways movements are limited, then you won't be able to use swings fully to adjust both the plane of focus and what is included in the frame.
     
  5. I recommend you read "The Camera" by Ansel Adams. View camera movements are discussed with respect to the Scheimflug effect, but more significantly, when and how to take advantage of that effect in an artistic sense.
     
  6. Thanks for your responses. I guess I really did ask a "dumb" question, in that I didn't think the question through enough before committing it to writing. I have done a fair amount of photography in my life, and yes I have read all Ansel Adams books and much on the Scheimpflug Rule (including Harold Merklinger's writings on the Hinge Rule). But sometimes reading stuff doesn't hold with me- I need to actually do the process several times before I understand it. For instance, I have always found it difficult to "imagine" or "visualize" the line where the film plane, the subject plane (plane of sharp focus), and lens plane converge, despite diagrams. I will do some more practice and play around with using the rear swing in conjunction with moving the camera around to see what happens. I think a big problem is just seeing clearly in the GG near the edges and corners- a problem that might be helped with a better GG, but not much. Also, it seems that I tend to over use the movements- swinging or tilting too much without realizing it greatly confuses the issue.
    Keith
     
  7. Keith, you've receive some good answers already. I will add some suggestions.
    I suspect that many beginners, when trying to setup a tilt or swing to control focus, adjust the standard to much too large of an angle. The advertisements that show LF cameras dramatically contorted are misleading. In most situations only a couple of degrees is all that is needed. Sometimes for tabletop photography larger movements are needed.
    The checklist / procedure from Howard Bond is useful: http://www.largeformatphotography.info/articles/bond-checklist.html.
    If you still feel lost about what angle of tilt or swing to use, Rodenstock makes an inexpensive "calculator" that will give you the answer. This is really a simple, non-electronic, plastic slide-rule like device. The calculator works well, but most experienced LF photographers use a visual & iterative approach like that of Howard Bond.
     
  8. You need a couple of tools to help with composition and focusing - a 4x to 5x loupe and a Fresnel lens to fit outside the GG. Check www.edmundoptics.com for inexpensive Fresnel lenses you can cut to fit. The Fresnel lens is a composition aid, but inteferes with focusing - therefore it should be easily mounted and detached.

    For Scheimflug effects, start simple. In nearly every case, you want the back to be vertical and the rail/bed level. You also want the back to be parallel to the plane of your subject, which you achieve by turning the camera, not the back, at this point (simple, remember).

    For landscapes, use the front rise to lower the horizon for better composition, and to avoid vertical convergence. Use the tilt (usually forward) to bring the foreground into the same focus as the background, but usually not both at once.

    For portrature, simply center the movements (keeping the back vertical), and raise or lower the whole camera to get the composition you want. Facial recognition is deeply ingrained in our brains. Even subtle distorion of the Scheimflug type tends to look odd.

    Most cameras, particularly folding cameras, exhibit yaw when you combine rise/fall with swing/tilt. With yaw, the axis of the lens is displace, greatly complicating the creation of desirable Scheimflug effects. Your main recourse is to KISS (keep it simple...), or get a good monorail (e.g., Sinar P or X).
     
  9. In the absence of a front swing, the goal of architectural correction of the mirror and achieving a desireable "plane of focus" may be mutually exclusive.

    As others have noted, back swing (& tilt) affects both geometry and focal plane. where as front swing affects focal plane position only.

    Your photograph as near as I can tell has a plane of focus which approximately coincides with the wall picture just left of the standing lamp and comes towards the camera at about where the area rug meets the wall to wall at the bottom edge of the picture.

    Given the above as the "center" of the plane of focus, the only way to improve the focus to each side of the plane of focus will be to stop the lens down.

    My normal practice in photographing is to place the plane of focus to intercept as many of the most important subjects as possible.
     
  10. pvp

    pvp

    Keith, the other responses are pretty much on the mark; rear movements affect both the geometry and the focus. In my own work, I find it helpful to remind myself that, no matter what movements I use, there will still be only a single plane through the 3-dimensional subject space which will be acurately focused on the film. The purpose of movements, then, is primarily (in my case) to minimize the focussing difference between the near and far. From there, the best that can be done is to stop down so the DOF brings the rest into acceptable resolution.
    It looks like you made the perspective correction you had in mind, and then forgot to critically check the focus after putting the swing into the mix (sort of confirmed by your belief "that the rear standard movements changed perspective but did not affect focus." Any camera movement will alter the location (in the subject space) of the plane of focus, so any time you change anything it is necessary to refocus.
    A 4 to 6 power loupe will help you to see what is actually sharp on the GG. Dig through Harold Merklinger's stuff at www.trenholm.org for some great info on how movements work. He has some animations that were very helpful for me.
     
  11. I only skimmed the responses. I'm probably repeating. Leslie Stroebel's "View Camera
    Technique" explains everything.
     
  12. Keith,

    " I have always found it difficult to "imagine" or "visualize" the line where the film plane,
    the subject plane (plane of sharp focus), and lens plane converge, despite diagrams."

    In regards to your statement above... I also had one heck of a time visualizing this.... until
    I came across a book called, "A Users Gide To The View Camera" by Jim Stone. Then, it was
    akin to a light being turned on. :)
    Anyway... give it a read. IMHO, it's well worth the time and effort!

    Cheers
     
  13. Keith,

    "would have swung the front standard to be about parallel to the rear . . . .? "

    Yes that would be analgous to your front and back tilts.

    If you think about a fixed lens camera like a 35 mm or something, the film is always parallel with the lens, or you might think of them the lens as on a central axis which is pointed at your subject, and the film is exactly perpendicular to this axis. Shooting with this situation with a lens wide open presents a very limited depth of field.

    Now if you think about swiveling the film out of perpendicular, you would see that part of the film is closer to the lens, and part of the film is further from the lens! If you had this set up pointed directly at a flat wall, of course parts of the wall will be out of focus.

    This is what the Scheimflug principle is all about. I use it to advantage for instance in landscape photography so I can focus close up on flowers in the foreground and also focust far on distant mountains simultaneously.

    For your situation, without replacing the Ansco, either use a front shift, which your camera might have. Or accept the distortion in favor of orientation of the plane of focus.
     
  14. Keith,

    Place the front standard parallel to the wall and shift the rear standard to where it needs to be rather than using swing. In other wards, you can swing the front standard by rotating the camera on the tripod. You then shift the back to frame your image. I have front swing and don't use it.
     
  15. The picture taken above does not have the back parallel to the right wall. If it were, the wall would be entirely square on the film. Keeping the back "vertical" produces straight vertical lines, to which most viewers are most sensitive. The other lines in the room of the two other walls would show convergences, with a vanishing point for each of the walls.

    Aesthetically, I like the current view point of the camera as well as the two point perspective. I think it is a lot more live than the staticness that would be created by having the wall with the mirror absolutely square. Of course if the wall has perspective, than so would the mirror.

    Perhaps you should use some correction such as you did in the example, but I don't suggest making the back completely parallel to the mirrored wall.
     
  16. Wow! Thank you all for such detailed and generous discussion!

    Two things: 1) I found out that for some reason I can not see properly with my Peak 10x loupe on the GG off center. I finally figured out that I can actually see better with a pair of "cheater" glasses or a magnifying glass rather than with the loupe. Also, I momentarily used a 600watt quartz lamp to shine on certain places in the scene where I needed to see clearly to check focus.

    2) I finally had luck using the advice given above: effectively swinging the front standard by rotating the camera on the tripod, then using the front shift to reframe.... I should have thought of that before, but it just wasn't in my previous experience, and not intuitive to this beginner (with using movements).

    I also really appreciate the references to Leslie Stroebel and Jim Stone's books, which I will look for.

    Thanks so much! What a great forum!
    Keith
     
  17. Keith,

    One of the problems with a 10x loupe is that it's probably too powerful for viewing the
    ground glass... you may want to consider using a 4x - 6x magnification loupe instead.

    My personal preference is the Toyo 4x loupe... or the Sylvestri tilting loupe.

    LF may be challenging (and darn frustrating at times) but.... it's ALL fun! :)

    Cheers
     

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