Glossary of 3D photography and stereography terms

3D photography. Photography that appears to have three dimensions, height, width, as well as depth. It does not really have depth because you cannot view the image from the sides or behind, but when viewed from the front, there appears to be depth with some objects behind other objects.

Anaglyph. A stereograph with two images on top of eachother. One image is red and one is blue. The images are then viewed through red and blue glasses. Other colors are sometimes used. Not he best way to view color images.

Cha cha. Taking stereo pairs with one camera by shooting one picture, then shifting your weight to the other foot and shooting another.

Free-viewing. Many people cannot view stereo pairs without the aid of a viewer. It takes some practice and can cause headaches in some people. Click here for instructions on freeviewing.

Holography. Invented in theory by Dr. Dennis Gabor at Imperial College of London in 1948, holograms were not practical until the ruby laser was invented in 1960 by T.A. Mainman of Hughes Aircraft. Today, holograms are made with lasers and produce images that one can practically touch. Some appear to float in space in front of the frame, and they change perspective as you walk left and right. Holograms are monochromatic, and no special viewers or glasses are necessary, although proper lighting is important. To make a hologram, lenthy exposures are required with illumination by laser beams that must be carefully set up to travel a path with precisely positioned mirrors, beam splitters, lenses, and special film. The technology moved rapidly in the 1960s, and in the 1970s a handful of artists began playing in hologram labs. Many of us expected Star Wars-like projections of holograms to be just around the corner, but the technology has not advanced much since then.

Hyperstereo. Hyperstereo is when the lenses are separated by more than 2.5". The feeling that one is looking through the eyes of a giant is often the result. This is done commonly for landscapes or images when objects are far away.

Hypostereo. When the lenses are separated by less than 2.5". This is common in macro, or closeup work.

Lenticulars. Remember the plastic baseball cards and Cracker Jack prizes with images that moved when you tilted them? Called lenticular prints, these cards are made of thousands of tiny plastic lenses and the images are layered so they can give the sense of dimension or motion.

Lorgnette. A handheld pair of lenses that helps people view stereographs. Plastic lorgnettes cost as little at $3, and quality glass lensed lorgnettes may cost $100 or more.

Magic Eye. Paintings and computer generated optical illusions that, if one can freeview, reveal hidden images of shapes and objects.

Ortho stereo. The ideal position and distance for viewing a stereo image.

Panorama pictures. Pictures taken of the world around you as if you were turning around in a circle. Click here to see examples.

Photo bubble or photo sphere or photo cube. A form of panorama picture made of photos usually taken with a fisheye lens. They are then stitched together to produce a photo sphere or cube. The viewer can see all around, above, and below. Click here to see examples.

Pulfrich stereo. Stereo video taken by rolling a camera sideways at a right angle to an object. When played back the viewer wears glasses with one eye unobstructed, and the other through a darker lens. The brain is fooled into processing frames of the video in sequence, and the result is a moving stereo image in color.

Realist format. 35 mm film images that are 24 x 23 mm. Regular 35 mm images are 24 x 36 mm.

Spinography. This is done by walking around an object and taking pictures every 10-20 degrees, or putting the camera on a tripod and an object on a turntable and rotating it 10-20 degrees between shots. It can also be done with 3D modeling software by a computer. It does not create the same sense of depth as stereographics. To view spinography on a computer you usually need a small program for your browser called a plug-in. Click here to see examples.

Stereo blind. A term describing people who cannot fuse two images into one with depth (stereopsis).

Stereographs or stereograms or stereopairs. Two images made from different points of view that are side by side. When viewed with a special viewer the effect is remarkably similar to seeing the objects in reality. Stereocards are stereopairs mounted on a piece of cardboard, usually 7" x 3.5". Click here to see examples.

Stereojet prints. Stereojet prints are startlingly beautiful. Made of a special transparency material with polarized images inkjetted onto each side, they can be displayed as transparencies or mounted against a reflective background and can be made up to poster size. They are viewed with an inexpensive pair of polarized lenses made for stereo viewing. Regular sunglasses will usually not work because the lenses are mounted at the wrong angle of polarization. Colors are truer than anaglyphs, and when properly lit, they look very real.

Stereopsis. The blending of stereopairs by the brain.

Stereo window. If a window pane were placed between the edges of a stereopair, the plane is called the stereo window. If the objects appear to be closer to the viewer than this plane it is called breaking the window.

VR or Virtual Reality. VR is a computer generated immersive realm that respond to interaction by the viewer. Usually the viewer wears goggles or a helmet, and often includes gloves and boots to simulate reaching, touching, and walking. As computers and imaging technologies improve, VR is approaching R. Many 3D tools are called VR, but they are not (see VRML). Although they allow you to see all sides of an object by rotating it, you are still seeing only two dimensions at a time.

VRML (Virtual Reality Markup Language). A set of standards for spinography software. Images are not really VR.