Stereo Photography
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People Pictures In 2D you can get away with portraits and group shots taken "head on" with everyone facing the camera. That's not good in stereo. But even in 2D a portrait is more interesting if the subject's body is seen from a 3/4 angle, even if their head faces the camera.
This picture shows violinist/violin-maker William P. Muller of Lewisburg, PA, with the "Cowboy Boot" violin he built as a joke. It has the shape of a cowboy boot, f-holes in the shape of six-shooters and a carved horse's head scroll. Its sound is excellent. The picture, however, has problems. The left-eye picture has flare from sunlight coming in windows in the wall just above the subject's head. The frame of the sound absorbing panel on the wall competes with the frame of the picture, and it is slightly tilted. Camera tilt is one thing you usually cannot correct in stereo pictures. You must have the camera aligned properly when the picture is taken. [Fuji 3d]
Backgrounds. The stereo photographer needs to pay attention to what's behind the subject, to ensure that it does not distract from the center of interest. If you use large apertures, the background may be so defocused that its details don't allow it to be recognized in 3d, and that may be desirable. But if it is only slightly unsharp, and has distinguishable detail, that unsharpness may annoy the viewer. You usually do not want a clearly rendered background so far distant that the eyes must adjust distance drasticaly to move from the subject to the background and back again.
In 2d one used to see pictures of people where a distant object, like a telephone pole or tree, seemed to extend from the subject's head. In 3d this same picture would clearly show that the distant telephone pole was not attached to the subject's head. Still, you would probably want to avoid that sort of juxtaposition. A more subtle effect can occur when a nearby object obscures part of a distant one, but only for one eye. It is best to have only featureless parts of the background contiguous to the subject. In Bob Muller's portrait above, the background frame comes a bit too close to the boot of the violin in the right-eye picture, and was worse in the picture I took just before this one. However, his head is well removed from background features, as it should be in stereo.
Natural Frames. Distant scenes don't show much stereo depth. If there's nearer objects in the scene, they can give the picture depth and scale. Perhaps some shrubbery or an overhanging tree branch can provide a natural frame for the scene. Best not to overdo it, though. The final picture shouldn't look "contrived". The example below may be overdone. [Fuji 3d, cropped.]
This is also an example of disturbing camera tilt. With so many vertical lines in the picture, one would rather see them parallel to the picture frame. In this case the camera was also aimed a bit upward, causing convergence of verticals. In that situation it is sometimes better to balance this so that those to the left of the scene and those to the right of the scene are tilted about the same amount, but in opposite sense. In this picture everything seems to lean leftward, and it can't be fixed.
Exploiting the Zoom lens. The Fuji 3d camera has coupled zoom lenses. This is a "first" in stereo cameras (with the exception of custom-built stereo cameras). Just as a zoom lens affects perspective in 2D, it also affects relative depth in 3d. In its "tele" setting it compresses (reduces) apparent depth. In its "wide" setting it exaggerates depth. You may have seen portraits taken at close distances with super-wide or bug-eye lenses. The subject's nose appears too large and the ears too far away. The modest 3x zoom of the Fuji 3d camera won't produce such extreme effects, but just as studio portrait photographers often use a 2X telephoto lens for portraits, you may find that moving back farther from your subject and setting the lenses on "tele" makes for more attractive portraits. The depth compression or exaggeration is a function of camera distance from your subject; it's not the fault of the lenses. If you moved twice as far from your subject, and took a photo at the "wide" setting, then cropped and enlarged the subject being photographed, the result would be look the same as if you had used a 2X telephoto from the same vantage point. But the picture would have less clarity and resolution. Learn to use the varifocus lens to your advantage.
The stereo shadow. |
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The Dreaded Stereo Shadow. Most cameras have a small supplementary "fill" flash built-in. The Fuji 3d has one directly between the lenses. When it is used for lighting nearby objects, or portraits, each lens sees the shadow of the subject on opposite sides of the subject. This is annoying in 2d, but much worse in 3d. Such subjects are better lighted with flash well away from the camera, or flash bounced and diffused from a white ceiling, or with carefully placed floodlights. In fact, the Fuji 3d camera does quite well in normal natural indoor lighting with its flash suppressed.
Even though the shadow effect is a result of using a 3d camera, the shadows are in 2d, which gives them indeterminate depth, and this is an added annoyance.
In 2d photography one might avoid flash shadows by positioning the subject well away from a background wall. But in 3d, a distant wall would distract from the subject, for your eyes would want to adjust from subject to wall and back again. A featureless wall is good, for it has no discernable distance.
A similar annoying effect occurs with cha-cha or slide bar stereos taken with on-camera flash. The flash moves with the camera, shifting the shadows on the background. That's not usually desirable. Keep an external flash in a fixed position relative to the subject. Move only the camera.
Off-Camera Slave Flash. The Fuji 3d camera has only a puny "fill-in" flash between the stereo lenses, which is of little use for stereo. The camera has no provision for connecting or synchronizing an external flash. The solution is to use a solid state flash trigger unit that fires a flash when it senses the camera's flash.
Be sure to choose a flash trigger or a slave flash that is designed for digital cameras so it ignores the weaker pre-flash that the camera uses to determine exposure. Be certain that the device specifications tell you that, or, better yet, take your camera to a store that sells flash slaves and test them before buying. I have tested the very inexpensive Neewer SF-01 digital slave flash. See it at Amazon.com. It works with most digital cameras on or off-camera and can be set to ignore 1, 2, or 3 pre-flashes.
The external flash should be bright enough to overpower the relatively small output of the on-camera flash. Information on use of external flash with the Fuji 3d camera is almost totally absent on the internet, and Fuji's instruction manual offers no help whatsoever.
Flash has a serious drawback in any kind of photographythe inverse square law, which makes the flash illumination decrease with distance. So with the flash anywhere near the camera, distant objects are too dark compared to nearby ones. Multiple flash units can help, just as multiple floodlights are used in a studio setting. Bounce flash from a white reflector, or from a white ceiling, can help reduce this effect. Outdoors, supplementary fill flash can help illuminate a nearby darker subject, such as a person in the shade of a tree. The techniques of effectively using flash illumination in 2d photography also apply to 3d photography.
Stereo Composition. After examples of stereo pictures that aren't perfect, here's one that comes close.
This restored historic Victorian farmhouse is at Montour Nature Preserve in Pennsylvania. After walking all around it, I found this vantage point that would give a picture that didn't include anything obviously modern: the bright red nature center building behind it, modern trash receptacles, informational signs, and an air conditioning unit. By choice of vantage point most of these could be hidden behind shrubbery, and one is located in an inconspicuous place. I probably took more care in choosing a camera angle than any other picture I took that day. Fortunately this choice also presented the building from a stereo-attractive angle, allowing the classical perspective of converging lines to support the stereo effect. Head-on stereo pictures of buildings are usually uninteresting. The curved foreground rock garden also helped the stereo. It was taken on an overcast fall day. [Fuji 3d]
This picture also illustrates why stereo photographs are not reality, but a miniature representation of reality. It is hard to escape the feeling that this house and its gardens are a miniature model of a house and garden. And this will be true with any method of viewing that presents the picture subtending a smaller angle than the camera sawparallel view, cross-view, computer monitor, etc. If this were projected on a screen some 15 or 20 feet wide, only then would it appear truly "real". If it were seen with a hand viewer having lenses of focal length equal to those of the camera, then it would reproduce the true 3d geometry, but no such viewers are yet available for digital pictures.
Try this experiment. Using cross-view, slowly bring your head closer to the monitor screen, and notice how the house seems to appear larger and the stereo depth greater. The picture begins to look more "real". But soon you get so close you cannot cross your eyes any more, and the picture is still not reproducing the true geometry of the original. In general you'd have to be about as far from the screen as the picture width to reproduce 3d reality. If you did this experiment with an autostereoscopic display, or with polarizing or shutter glasses, you'd begin to see individual pixels as you get closer, which would degrade the stereo effect. Next time you see stereo pictures projected on a screen, try walking closer to the screen, and notice this phenomenon.
Here's an example that I deliberately photographed to illustrate the problem. The foreground flowers are attractive enough, but the distant mountain slope just has too much stereo parallax. It is distracting and creates eyestrain. The Fuji 3d camera doesn't allow you the option of throwing it completely out of focus. Look for opportunities to have nearly featureless backgrounds not far behind your main subject.
Here's more general Guidelines for Stereo Composition.
Input and suggestions are welcome at the address shown to the right.
All stereo pictures on this page © 2009 by Donald E. Simanek.
Stereo pictures for cross-eyed viewing 3d Gallery One.
More cross-eyed stereos in 3d Gallery Two.
Stereo view cards in 3d Gallery Three.
Building a digital stereo close-up photography system in 3d Gallery Four.
Review of the Loreo stereo attachment 3d Gallery Five.
Review of the Loreo macro adapter, 3d Gallery Five B
The Loreo macro stereo attachmentimproved 3d Gallery Five C.
The Loreo LIAC attachment as a 3d macro device, 3d Gallery Five D.
Wildlife photography in your backyard, 3d Gallery Six.
A home-built digital stereo camera using mirrors 3d Gallery Seven.
Stereo close-up photography in your garden 3d Gallery Eight.
Stereo photography in your aquarium 3d Gallery Nine.
Stereo digital infrared photography 3d Gallery Ten.
Wider angle stereo with the Loreo LIAC 3d Gallery ll. A failed experiment.
Review of the Fuji FinePix Real 3D W1 camera 3d Gallery 12.
Macrophotography with the Fuji 3D camera. 3d Gallery13.
Panoramic stereo photography. 3d Gallery 14.
Mirror methods for stereo photography. 3d gallery 16.
The Fuji 3d macro adapter using mirrors, by Paul Turvill.
The Fuji 3d macro adapter with flash! 3d gallery 17.
Critters in stereo. 3d gallery 18
Wide angle stereo. 3d gallery 19.
Telephoto Stereo. 3d gallery 20.
2D to 3d Conversion. 3d gallery 21.
Stereos from outer space. 3d gallery 22.
Review of the Panasonic Lumix 3d digital camera. 3d gallery 23.
Reverberant flash for shadowless lighting.
Digital stereo photography tricks and effects.
Shifty methods for taking stereo pictures.
Stereoscopy with two synchronized cameras by Mike Andrus.
Guidelines for Stereo Composition.
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