Stereo photography techniques

The invention of photography in 1839 opened up a new and more detailed medium for his experiments and the first photographic stereoscopic pairs appeared in the early 1840s as Daguerreotypes and Calotypes.

By the 1850s, a stereoscope and an assortment of professionally photographed stereo views were becoming part of the standard equipment of a properly furnished middle-class parlor.

The earliest were inconveniently large and the result was a pair of paper prints mounted on a card for viewing in a standard stereoscope.

In the late 1940s, compact imported European stereo cameras that used 35 mm slide film began appearing in the US market.

The camera was not actually available for purchase until 1947, but the ads generated a lot of excitement among stereo photography enthusiasts.

[3] By 1952 several competitors were already marketing their own cameras using the 5P format, making it the de facto US industry standard.

The relative novelty of Kodachrome's vivid colors and the realism of 3-D were each attractive individually, but the astonishingly lifelike effect of the two combined proved irresistible to many consumers.

The new cameras were marketed with corresponding two-lensed Realist-format slide viewers, which typically had a built-in light source and adjustable optics.

Unlike the pop culture 3D fad, which came and went quickly and was primarily a 1953 phenomenon, the popularity of amateur stereo photography started earlier, grew more slowly, peaked later, and declined more gradually.

Subsequent decades found new users replenishing the ranks of loyal devotees and supporting a solid market for second-hand equipment.

The original Loreo was the pioneer,[8] but it was followed by several other cameras, including some designed to take macro shots.

[9] It is also sometimes referred to as the "astronaut shuffle" because it was used to take stereo pictures on the surface of the Moon using normal monoscopic equipment.

When these images are viewed using high quality viewers, or seen with a properly set up projector, the impression is, indeed, very close to being at the site of photography.

One way of dealing with this situation is to include a foreground object to add depth interest and enhance the feeling of "being there", and this is the advice commonly given to novice stereographers.

This will effectively render the captured image as though it was seen by a giant, and thus will enhance the depth perception of these distant objects, and reduce the apparent scale of the scene proportionately.

[12][17] It is also possible to take hyperstereo pictures using an ordinary single lens camera aiming out an airplane.

[30] Similar techniques were used late in the 19th century to take stereo views of Mars and other astronomical subjects.

On the other hand, in the case of a massive ship flying through space the impression that it is a miniature model is probably not what the film makers intended!

In the red-cyan anaglyph example to the right, a ten-meter baseline atop the roof ridge of a house was used to image the mountain.

In the wider image below, taken from a different location, a single camera was walked about one hundred feet (30 m) between pictures.

Pepax, thought to be an amalgamation of PErspective and PArallaX,[36] involves the use of a wider than normal baseline, but for a different purpose.

Because the size of objects is increased in proportion to the enhanced depth, there is no miniaturization effect as with hyperstereo, but the same telephoto compression seen in extreme zoom flat photographs also occurs.

[38] When objects are taken from closer than about 6 1/2 feet a normal base will produce excessive parallax and thus exaggerated depth when using ortho viewing methods.

When still life scenes are stereographed, an ordinary single lens camera can be moved using a slide bar or similar method to generate a stereo pair.

[40] In recent years cameras have been produced which are designed to stereograph subjects 10" to 20" using print film, with a 27mm baseline.

When images are viewed on a small screen from a short distance, differences in parallax are smaller and the stereo effect is muted.

When images are intended for anaglyph display a muted stereo effect generated by a smaller baseline will help to minimize "ghosting" artifacts.

Achieving this could be as simple as using the 1:30 rule to find a custom base for every shot, regardless of distance, or it could involve using a more complicated formula.

While geometric stereo neither attempts nor achieves a close emulation of natural vision, there are valid reasons for this approach.

The precise methods for camera control have also allowed the development of multi-rig stereoscopic cameras where different slices of scene depth are captured using different inter-axial settings,[45] the images of the slices are then composed together to form the final stereoscopic image pair.

Modern stereo TV camera
The Stereo Realist, which defined a new stereo format. The middle lens is for view-finding.
Sputnik stereo camera (Soviet Union, 1960s). Although there are three lenses present, only the lower two are used for the photograph – the third lens serves as a viewfinder for composition. The Sputnik produces two side-by-side square images on 120 film .
Illustration of parallax multiplication limits with A at 30 and 2000 feet
Small anaglyphed image 3D red cyan glasses are recommended to view this image correctly.
Long base line image showing prominent foothill ridges; click the image for more information on the technique 3D red cyan glasses are recommended to view this image correctly.
A mineral specimen imaged with scanner. Anaglyph, red left.