1. A method of correcting luminance non-uniformity in a tiled projection system comprising; projecting with a plurality of projection devices a composite image wherein the composite image comprises a plurality of tiled images on a display surface with an overall luminance, each of the plurality of tiled images being projected by an associated first projection device and an associated second projection device redundant with the associated first projection device; and correcting a luminance non-uniformity of the plurality of tiled images, wherein the luminance non-uniformity is based on a dimmed at least one of the plurality of tiled images resulting from a first energy output of the associated first projection device associated with the dimmed at least one of the plurality of tiled images, wherein correcting the luminance non-uniformity comprises raising energy output of the associated second projection device associated with the dimmed at least one of the plurality of tiled images.