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What do cosmology and 3D imaging have in common? If you know the answer is they both exploit light bending, you need not read further.

With it's publication, Einstein's Relativity theory predicted gravity could bend light. Because the gravity needed to do so was so intense, everyone ignored it, thinking it had no practical use. But once astrophysicists integrated computers into their telescopic imaging, this nearly forgotten phenomenon opened the universe wider.

Earlier, only galaxies that had no obstructions between them and Earth's telescopes could be imaged, leaving millions of galaxies hidden behind them, unseen. Computers, analyzing the light around a galaxy's edges that shone toward Earth, could extract out light that beamed straight toward Earth and light that had been bent by the enormous gravity of the viewable galaxy. Isolating the bent light, that is, the light beaming from a galaxy behind the visible one, astrophysicists could then image the hidden galaxy(s).

Note that in the image above, no light source is behind Delilah, and yet, she is clearly visible and not a dark silhouette. That is because the front two emissives' light, beaming toward the camera from around her edges, are illuminating her as they move past. Indeed, along her spinal area you can see the remnants of a silhouette.

This is the digital equivalent of light 'bending'. The technique in effect replaces a Fill light's function and, of course, no Key light is present.

The effect requires two things. One, the lumens must be turned way up. Otherwise, the light beams traveling just past the character/object's edges will not have sufficient strength to provide indirect illumination. Note the seat cushion is washed out. Second, the light source's position will have to be angled toward the character/object but leave enough room for light beams to travel without interference around the character /object's edges.

In the scene above, the two Emissive lamps on either side fulfill these requirements. There is also a standard Spot facing Delilah head on, which if used alone, would have made her a silhouette.

For those interested, the link below is for another image titled 'Pas de Deux' also utilizing this technique.

www.deviantart.com/rtesian/art…