3D Photography

My fascination with 3D photography began after seeing View-Master photos ( http://en.wikipedia.org/wiki/View-Master ) as a kid. About 3 years ago I decided to make my own 3D photos.
I met a photographer, who was taking 3D photos, at a meet-up photo shoot at the Fortress of the Arts in the Philadelphia. (http://www.meetup.com ). He used two point and shoot pocket Canon cameras to capture the images, processed them with Stereo Photo Maker (http://stereo.jpn.org/eng/stphmkr/ ) and converted the left and right images to stereo anaglyph photos for viewing with red+cyan glasses on the meetup photo album.

I had a Canon SD800 pocket camera already, so I bought an identical used camera on eBay. The Canon firmware has a hack (http://chdk.wikia.com/wiki/CHDK ) that allows remote control of the camera using the USB port. On the web I found a circuit for controlling two cameras together. I merely replicated what others have accomplished with the Canon camera. After loading the firmware hack, I was able to shoot left and right photos with the cameras mounted on a homemade bracket. My bracket was an aluminum bar, but others use Z-bars, that allow the lens to be spaced closer.

The Stereo photo maker software is the key to converting left and right images to stereo photos. We owe a huge debt of gratitude and thanks to the author, Masuji Suto for this free software. Without it would a lot harder to create 3D photos.

I wasn't satisfied with the SD800 camera for creating stereo photos, because I want to use off camera flash Since I already owned a Nikon D80, I bought another used Nikon D80 on eBay for stereo work. My Nikkor 50 mm 1.8 prime lens produces exceptional images and is inexpensive, so I bought a 2nd for the stereo setup. I wired the shutter release control circuit using a diode OR circuit that can be found on the web and put it  into a Radio Shack box. The idea is to not let the cameras interfere with each other using a single shutter release button. The camera shutter release controller cables were bought from CameraAxe (http://www.dreamingrobots.com/store). I also bought a CameraAxe 3 controller kit, but that's another story.

The 50 mm lens functions like a 75 mm portrait lens on a DX camera such as the D80 (an advantage for doing portraits). Since my cameras are mounted horizontally, lens spaced 170 mm apart, I had to be 20 feet from a standing model, but the best stereo images had the model around 12 ft from the camera. With stereo I wanted a large depth of field, so shooting at F11 often required a slower shutter speed. The cameras were mounted on homemade bracket placed on a tripod. The menu settings and manual controls on both cameras had to be set identical.

I discovered you can achieve greater depth of field with a wide angle lens and get better stereo photos. Since I had a kit Nikon DX 18-55 mm lens already, I got a second. With this lens I tend to use 18 or 24 mm settings and get really good depth of field at F11. It is best to auto focus the main subject with one camera and then set this camera to manual focus, and repeat with the second camera pointed at the subject. Then rotate the cameras to compose the scene you want staying in manual focus mode.

This all works well when you keep your subject in focus and use natural light. But in a studio setting I want to use studio strobe lights. I mounted a pocket wizard on one camera to fire the studio strobe. Unfortunately the shutter release in the camers is not always simultaneous with lag time unpredictable with the D80 mechanical shutter. It can be off by 5 ms or more leaving the camera without the pocket wizard to miss the flash entirely, or sometimes you get a half exposed or underexposed photo. Seems that the more the cameras are used in a session, the more they get out of sync. Only half the photos were useable during one shoot, but I got enough good images to make a video of the results. Here is my model Jen Merritt.

Now I use two portable off camera flashes, mounted on a single umbrella, triggered separately by each camera. I find that most photos are exposed OK and can be adjusted to match using Stereo Photo Maker later. It's not possible to use the studio strobes at meet-ups in this way since they are shared with other photographers during the shoot.

For display I normally convert to red+cyan anaglyphs for viewing on the web. I also have a stereoscope that I can view side by side images on my computer screen. Sometimes I'll print a photo and view side by side with the stereoscope.

There is a lot to learn about 3D photography, so I bought a few books and joined the National Stereoscopic Association http://www.stereoview.org/ which has a “Stereo World” publication. I'll share more about 3D later.

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