1. A method for efficiently categorizing images on a computer system, comprising the steps of: (a) ordering a series of related images that are to be categorized by time of capture; (b) displaying category levels for input of category information by a user, wherein the category levels include a highest-category level and a lowest-category level, the highest-category level having a low frequency of data change between the series of related images, and the lowest-category level having a high frequency of data change between the series of related images; (c) categorizing a first image by allowing the user to enter highest-category level data and lowest-category level data; (d) categorizing a next image in the series by leaving the highest-category level data unchanged, and automatically selecting the lowest-category level data for reentry by the user, thereby eliminating the need for the user to reenter the highest-category level data.