A method for use in an imaging system having an image source and a plurality of microtile units for generating respective portions of the image is provided, each microtile unit including a self-contained screen and a rear projector for projecting the image on the screen, the method for at least one of self-aligning, colour matching and brightness matching the image portions across successive adjacent microtile units. The screen is over-scanned so that a portion of an edge of each image spills over onto a side wall of the microtile unit adjacent a further one of microtile units. Light from the image is permitted to spill through the side wall into the further microtile unit. The light is detected within the further microtile unit. The image is adjusted in response to detection of the light within the further microtile unit so as to at least one of align, color match and brightness match the image between the plurality of microtile units.