Quote - Captain - that sound's great.  Are you saying that if I use background and simply open an equirectangular image, it will work as if I were in the center of a sphere?  If so, how does one adjust lighting of the background?

It does indeed. I do find that a lot of equirectangular images in the background seem to be too close to the scene, so I often have to adjust the zoom on the camera before I starting bringing in objects.

As far as I know, you can't adjust the lighting of the background, except by gamma correcting the whole image. On the other hand, you can use the background image to light your scene, by turning on the "Sky Light" GI function (which is slow, but gives really accurate lighting, especially if your image is HDR).

Quote - Does this work for stereographic images?

Hmmm... I really don't know about that one. Couldn't hurt to try it, though.