Last time we discussed this, bloodsong pointed our attention to the theory that Distance Falloff was effected by the focal length of the camera used to record the scene via the scale of the camera. Atleast, that's how I understood it. Nance brought up the 'Vertigo effect' as a special case where this may cause a problem. A combination of boredom and curiousness drove me to recreate the legendary shot first devised by Sir Alfred Hitchcock (and any technicians that may have been attached to the discovery).

A 190kb QuickTime 4 movie file can be viewed here here.

Details:

As you will see in the above image, after animating the focal length of the Dolly Camera from 35mm to 22mm and moving the camera forwards (down on the Y axis in this case) by a distance of 1.000, it turns out that no adjustment of the distance fall off of Light 1 was necessary. I'm planning on making some adjustments to this test to allow for a greater change in focal length, but it seems to me that focal length has no effect on falloff or any parameters of a spotlight. So, I quote myself when I ask...

"What am I doing wrong?"