A method for generating a presentation of a region-of-interest in an original image for display on a display screen of a client coupled over a network to a server, comprising: establishing a lens having a focal region for the region-of-interest at least partially surrounded by a shoulder region; if the lens is in transit between first and second locations for the region-of-interest in the original image, applying the lens to the original image by a first method to generate the presentation at the client; and, if the lens is stationary in the original image, receiving the presentation from the server, the server applying the lens to the original image by a second method to generate the presentation.