3D Shadow Photography

2D Photo of Ceiling Lamp and its Shadow

When I shoot a 3D photo of a scene, the shadow of the subject in the image has no volume, only depth. I realize this is because there is usually only one light source producing the shadow. In everyday stereo vision, shadows have no volume. 

There is one exception I am aware of and it is discussed in a Wikipedia article  "shadow". There is a sub-section about three-dimensional shadows https://en.wikipedia.org/wiki/Shadow#Three-dimensional_shadows. A shadow with volume may occur in a fog. Unfortunately the photo illustrating this was not shot in stereo. I recall seeing this phenomenon only twice, ever, so it is a very rare sight.

We create stereo images with two left and right eye cameras or one camera shooting sequential left and right eye images. By analogy I got the idea to use two flash strobes (simulating left/right eye) spaced apart to simulate stereoscopic shadow vision. In my first experiments, I created 3D photos with three-dimensional shadows by using two light sources and alternating between shooting left and right eye shadow photos with a static subject.

In the example photos of the ceiling lamp, the camera is stationary on a tripod, and two shots were taken using the left and right eye spaced off camera flash strobes to produce the shadows in the 3D photo. I used a PocketWizard Plus II to trigger each the flash strobe separately with two different channels. The left and right photos were aligned with Stereo Photo Maker. The ceiling lamp subject is 2D and its shadow is 3D. Here is the result:

In the above photo the shadow appears on the wall.

Here is the same photo with left and right eye views swapped.

In this photo the shadow appears in front of the ceiling lamp.

Here are the anaglyph 3D stereo versions:

Because the ceiling lamp is semi-transparent and not solid, the volume of the lamp is more apparent.

This was my first experiment with 3D shadows. Later I created 3D photos where both subject and its shadow are in 3D stereo and the shadow has volume. That discussion is for another blog posting.