1. A computer-implemented method for displaying a portion of a high-resolution image in the context of a base-resolution image, wherein one or more processors are programmed to perform the steps comprising: receiving a request to view an image at a client device; sending a request to a server over a network for a base-resolution image that corresponds to the requested image; receiving the base-resolution image from the server over the network; displaying the base-resolution image on a display of the client device; receiving a request to display an area of interest of the base-resolution image in high resolution; sending a request to the server over the network for a composed image that corresponds to the base-resolution image; receiving the composed image from the server over the network; and displaying the composed image on the display of the client device.