1. The method of forming an image map of a specimen based on properties of points on the specimen comprising: supporting the specimen on a stage; irradiating the specimen from a source and simultaneously detecting the resulting radiation from a particular point on the specimen at a plurality of different wavelengths to generate a first set of electrical signals having values representative of properties of said point; repeatedly translating the stage relative to the source to modify the point on the specimen from which the radiation is detected to generate a plurality of additional sets of electrical signals having values representative of the properties of other points on the object; processing each of the sets of signals to compare each subset on a multi-variate statistical basis with one of a plurality of spectral signatures representing differing properties; and generating a two-dimensional array of elements, each element having a position in the array which correlates with the position of one of the points on the specimen and each element having one of a plurality of forms dependent upon the signature with which the set of signals based on that point most closely compares as a result of said multi-variate statistical comparison process.