For the stereo photographer film or digital!

DrT's HyperBar

For Hyperstereos with Twin Cameras

32 Inch maximum camera separation!

I think I have created the ULTIMATE hyperstereo twin camera bar!

Consider these features:

32 inch maximum camera separation in a compact lightweight bar, a hyperstereo maker's dream!

Camera are attached to platforms and can slide from one end (touching each other), to a separation of 20 inches (while still attach to the platforms - you need to take them off the platforms to get them 32 inch apart)

Can be attached to a tripod.

Graduated (in inches from 0 to +12 and -12 inches) makes it each to achieve a specific camera separation.

Two bubble levels can help align the bar vertically and horizontally.

Lightweight, only 12 oz, yet sturdy enough to support two standard SLR cameras.

You can use this bar to hold two standard camera (either film or digital) and record stereo pairs.

An extra platform is included. I can supply extra screws for $5 ea. (Made by Hama, Germany, they are not cheap!)

View from the top, notice graduated scale, & twin platforms.

View from the bottom - screws can attach to tripod

Cameras 10 inches apart (25 cm)

Cameras 20 inches apart (50 cm)

Maximum separation, cameras 32 inches apart! (81 cm)

The following information is provided for free. Remember: if you are in doubt, you can bracket stereo base, just as you bracket exposures in photography.

Stereo Base = Separation of recording lenses.

Normal (Ortho) Stereo = Stereo pair recorded with lens separation (stereo base) approximately equal to the spacing of the eyes (65mm, or 2.5 inches)

Hypostereo = Stereo pair recorded with stereo base smaller than the spacing of the eyes.

Hyperstereo = Stereo pair recorded with stereo base wider than the spacing of the eyes.

The twin camera bar offered for sale here will generally be used for hyperstereos. Even if you bring two film cameras as close as possible (touching) the lenses are about 4 inches apart. Compact digital cameras can be brought closer together. If you start separating the cameras, you increase the hyper effect.

Hyperstereo impression: Hyperstereo makes things look smaller. For example, if you photograph a building or a city with a stereo base equal to 10 times the spacing of the eyes (25 inches) then this building or city will appear as a small scale model (1/10) of the original building.

If the closest object to the camera is far away, a hyperstereo is the only way to introduce depth to the stereo pair.

1/30 rule of thumb: If you can change the stereo base (when using twin cameras on a slide bar like this one) then a good starting point would be to have a stereo base equal to 1/30 of the distance of the nearest object (instead of 1/30, some people use 1/FL where the FL is the focal length of the recording 35mm lens).

For more information about taking stereo pictures with a single or twin cameras, see my Stereo Tutorials.

How can you connect two camera so that they fire simultaneously? Some people just use their fingers and press the shutters at the same time. This technique is used often for digital cameras, which are not very easy to twin. More complicated systems for twining certain digital cameras are available but I am not an expert in this area.

Older mechanical cameras can be twinned using a twin mechanical cable. You can find these for about $40-$50. They are not perfect, but generally they are better than using your fingers.

Newer electrical cameras can be twinned by splicing together two electrical cords. This method is not perfect either because of delays associated with the internal workings of these cameras, but generally synchronization of up to 1/250 can be achieved most of the times.

When I use twin film cameras, I always set the cameras in manual exposure.

Should you converge the camera lenses, or leave them parallel? In general, it is recommended that the lenses are kept parallel to eliminate keystone distortion. However, in certain situations, (to set the stereo window in the pair or to increase image overlap) they can converge. Just experiment for yourself.

I welcome feedback and comments from buyers/users of the HyperBar!