1. A method for calibrating one or more projectors, comprising: displaying, via a first projector, a first projected image on a screen; displaying, via a second projector, a second projected image on the screen, thereby defining an overlap region whereby the first projected image and the second projected image overlap on the screen; selecting a first plurality of correspondences corresponding to the first projector and displaying the selected first plurality of correspondences with the first projected image in the overlap region on the screen, the first plurality of correspondences comprising four or fewer correspondences; selecting a second plurality of correspondences corresponding to the second projector and displaying the selected second plurality of correspondences with the first projected image in the overlap region on the screen such that the each of the first plurality of correspondences displayed on the screen overlap with and correspond to a respective one of the second plurality of correspondences displayed on the screen, the second plurality of correspondences comprising four or fewer correspondences; determining a first mapping from the first projector to the second projector using the selected first plurality of four or fewer correspondences displayed on the screen and the overlapping selected second plurality of four or fewer correspondences displayed on the screen, thereby defining a common coordinate system among the first projector and the second projector; selecting a third plurality of correspondences corresponding to points on the screen, at least one of the third plurality of correspondences corresponding to a corner of the screen and being outside of the overlap region; and determining a second mapping from the common coordinate system to the screen using the selected third plurality of correspondences; displaying, via both the first projector and the second projector, an image on the screen based upon the first mapping and the second mapping.