As it mentions at the end of the article, this technique can be used in artificial rendering (such as raytracing), as well. I’ve seen some impressive examples used to fake prismatic refraction (which is what gives diamonds their particular “sparkle”, for instance). You render three times, once with just red lights, then with just green, then with just blue. For each render, you alter the IOR (index of refraction) of the diamond object. Then you combine the three channels into a single image, which will then contain a reasonable facsimilethe rainbow effects that regular raytracing can’t reproduce without a lot of added complexity.
Making Dougal Campbell’s wish come true…an example for his rainbow effects tip is at http://www.sgi.com/misc/grafica/synth in an article titled Synthetic Lighting for Photography.
3 Comments
Mark on July 6, 2004 at 3:54 pm.
The weird thing is that I now read and enjoy the photography stuff you post on your blog.
Dougal Campbell (29 comments.) on July 6, 2004 at 3:56 pm.
As it mentions at the end of the article, this technique can be used in artificial rendering (such as raytracing), as well. I’ve seen some impressive examples used to fake prismatic refraction (which is what gives diamonds their particular “sparkle”, for instance). You render three times, once with just red lights, then with just green, then with just blue. For each render, you alter the IOR (index of refraction) of the diamond object. Then you combine the three channels into a single image, which will then contain a reasonable facsimilethe rainbow effects that regular raytracing can’t reproduce without a lot of added complexity.
I wish I had a link to an example….
Kenia Kraus on August 27, 2005 at 1:01 am.
Making Dougal Campbell’s wish come true…an example for his rainbow effects tip is at http://www.sgi.com/misc/grafica/synth in an article titled Synthetic Lighting for Photography.