I saw Harry Potter 6 in 3d, and most of it wasn't actually 3d, maybe only 20 minutes of it. How much of Transformers 3 is actually shot in 3d? I guess what I mean isn't how much is shot in 3d, but how much of the film will you notice the 3d. The Harry Potter film I saw, we were only told to put on our glasses for about 20 minutes of the film.
Edit: Well, for Transformers 3 I found a decent amount of noticeable 3D, probably a good 3rd of the film. I did see it in IMAX which may have helped the effect due to the larger screen and I sit in the lower to lower-mid section of the theater.
in fact it has some of the best effects ive seen since "A Christmas Carrol" where the snow seemed to fall around me