Puggo - Jar Jar's Yoda said:

So, when a movie is shot in 3D, and then "down-converted" to 2D, are areas of the frame chosen to be "blurred" to simulate the depth of field, after-the-fact?

That's what I personally would prefer. But I never saw such a thing, because every 3D movies I saw were shot as a regular 2D movies, meaning with depth of field (on both stereo pictures). A previous poster said that it should be doable to shoot a movie with no depth of field (but technicaly maybe difficult) and that it should be doable to convert it in 2D with depth of field by using the differences between the 2 stereo pictures of the 3D to recreate the blur. At least that's what I understood. the problem would be that in this case almost all the shots would be filled with depth of field effect if you can't specificaly choose what parts of the screen you want to be blurred or not, lol, brain explodes. Must go to bed.