1. A method comprising: receiving an image data set that comprises a multidimensional property space and data classifiable into data classes; determining a projection vector for data of the data set wherein the projection vector maximizes a ratio of between-class scatter to within-class scatter; selecting a reference for the vector; projecting at least some of the data onto the vector; measuring distances from the reference to at least some of the data; classifying at least some of the data into data classes based on a nesting analysis of the distances; eliminating the classified data from the image data set to produce a modified image data set; and deciding whether to determine another projection vector for the modified image data set.