1. An image data storage system comprising: a computer comprising a data compressor receiving original image data representative of multiple different images and compressing said original image data in order to generate, for each image, multiple resolution levels of compressed image data with each level representative of a progressively lower resolution copy of said image; and a disk drive array receiving, from said computer, said original image data and said multiple resolution levels of compressed image data, said disk drive array comprising at least one disk drive, each disk drive having a center and multiple tracks encircling said center, and each track being sub-divided into multiple sectors, and said disk drive array storing said original image data and said multiple resolution levels of compressed image data for all of said images such that, on any given disk drive, sectors positioned a track closest to said center store lowest resolution level image data and other sectors positioned on tracks farther from said center store higher resolution level image data.