I have two eyes. And because of that simple fact, I also have stereopsis, the ability to perceive depth. When I was about 7 years old, I gazed into a View-Master toy and saw an amazing three-dimensional picture, and I was hooked. Today, I create 3D videos, using various homebrew camera rigs and displays. I’ll introduce you to a few of my devices, but first, a quick history lesson.

In 1838, British scientist and inventor Sir Charles a pair of photographic flash bars with handgrips, Wheatstone theorized that seeing with two eyes salvaged from a flea market dollar bin, and created together is what allows us to see in 3D. Wheatstone a “handlebar” stabilizer. This allows me full mobility deduced that each eye observes a slightly different with the rig, and puts the center of rotation between view of the world, and our brain fuses these two the two cameras. perspectives together, interpreting the parallax To control recording, I use a device called the differences as depth. He called his discovery stereo- 3D LANC Master. Developed by Dr. Damir Vrancic scopic vision (literally meaning “to see solid”) and of Slovenia, the 3DLM connects the cameras via built an optical device, the stereoscope, that allowed the LANC ports and provides simultaneous control three-dimensional viewing of pairs of drawings. of most camera functions. It also keeps the video

With the invention of photography, and later recording in sync by continuously polling the tim-cinema, real-life images could be captured with two ing frequency of one camera, and adjusting the lenses and viewed in 3D. The popularity of stere- frequency of the other up or down to prevent drift. oscopy has persisted over the years. In the 1890s, This is very important when shooting 3D, as any arcades offered 3D peep shows as entertainment, time disparity between the camcorders will result and the handheld stereoscope was a common item in nonmatching left and right views. Schematics in home parlors — the TV of the Victorian era. The and software for the 3DLM are open source under 1950s and 1980s both saw 3D movie “booms” come a GPL and are available for free. and go, due to the technical limitations of the times.

And currently, in the age of digital video, stereoscopic 3D is seeing a major rebirth.

My own foray into 3D video began a few years ago, after I attended the monthly meeting of the Stereo Club of Southern California. Many of the photographers at the meeting had pairs of digital still cameras mounted side by side for shooting 3D photos, and it occurred to me that I could build a similar hand-held rig for use with small camcorders.

Shooting 3D

Starting with a pair of Sony Handycams, I set out to build a stereoscopic rig. My plan was to make the distance between the lenses, called the interaxial, equal to my interocular, or the distance between my eyes. This would give a natural-looking 3D depth to my footage, and would allow me to view 3D while shooting, just by looking through both camera’s viewfinders. Putting the lenses so close required removing the hand strap from the left camera.

I attached the cameras to a metal bar using quick-release mounts for easy removal, in order to access the tape and battery compartments. I fashioned a bracket from some spare parts to hold both cameras securely at the top and keep the lenses aligned. Inspired by director Mike Figgis’ steering wheel-like camera stabilizer (the “Fig Rig”), I bolted together

Viewing Live 3D

With my camera setup complete, my next task was to build a portable stereoscopic video monitor, so others could watch live 3D during shooting. In movie theaters, stereopsis is achieved by projecting left and right images through two oppositely oriented polarizing filters onto a reflective screen. By viewing through 3D glasses made from matching polarizers, each eye sees only the corresponding projection. I decided to use the same principle for my monitor.

I started with two small LCD monitors capable of showing NTSC video, the kind that are strapped to the back of car headrests. The video output from each camera is input to one of these monitors. Because LCDs have a polarizing layer, these displays appear black to one eye and visible to the other when viewed through polarized 3D glasses. I found that the monitors had a clear plastic protective sheet glued over each LCD. These had to be carefully peeled up and removed, as they were depolarizing the light from the screens.

On one display I needed to flip the picture horizontally like a mirror image, so I opened the case and wired pin 62 of the PVI-1004C LCD controller chip to ground. I attached the LCD displays to each other at a 90° angle, their screens facing inward, and mounted a piece of half-mirrored glass between

Make: 51