A technique and system for detecting a radiometric variation/artifacts of a front-projected dynamic display region under observation by at least one camera. The display is comprised of one or more images projected from one or more of a plurality of projectors; the system is preferably calibrated by using a projective relationship. A predicted image of the display region by the camera is constructed using frame-buffer information from each projector contributing to the display, which has been geometrically transformed for the camera and its relative image intensity adjusted. A detectable difference between a predicted image and the display region under observation causes corrective adjustment of the image being projected from at least one projector. The corrective adjustment may be achieved by way of pixel-wise approach (an alpha-mask is constructed from delta pixels/images), or bounding region approach (difference/bounding region is sized to include the area of the display affected by the radiometric variation). Also: a technique, or method, for detecting a radiometric variation of a display region under observation, as well as associated computer executable program code on a computer readable storage medium, therefor.