A computer-implemented method of image processing for materials analysis comprising performing the following set of steps automatically:- a) obtaining N image datasets, each dataset representing intensity values of image pixels, wherein the image pixels represented by the datasets are in a common spatial registration, and wherein N is an integer greater than 3; b) processing the N image datasets so as to assign a comparison measure to each pair of image datasets, the comparison measure for a given pair of image datasets being representative of the difference between the spatial intensity information within one image dataset in comparison with the spatial intensity information within the other image dataset of the pair; being characterized by c) selecting a number of the image datasets based upon the comparison measures; d) defining a colour difference measure which represents the difference between pairs of colours of a colour set; e) assigning a colour to each of the selected image datasets such that pairs of the selected image datasets which have different spatial intensity information between datasets within a respective pair, are assigned respective colours which have a different colour difference measure; and, f) combining a number of the selected image datasets together to form an output colour image dataset for the formation of a colour image such that each pixel of the colour image takes on a colour according to the relative intensities and colours of the said number of selected image datasets so that if the pixel intensity of one dataset is greater than the sum of the pixel intensities for all the other selected datasets, the output colour in the respective part of the image will match the colour assigned in step (e) to that image dataset. a) obtaining N image datasets, each dataset representing intensity values of image pixels, wherein the image pixels represented by the datasets are in a common spatial registration, and wherein N is an integer greater than 3; b) processing the N image datasets so as to assign a comparison measure to each pair of image datasets, the comparison measure for a given pair of image datasets being representative of the difference between the spatial intensity information within one image dataset in comparison with the spatial intensity information within the other image dataset of the pair; being characterized by c) selecting a number of the image datasets based upon the comparison measures; d) defining a colour difference measure which represents the difference between pairs of colours of a colour set; e) assigning a colour to each of the selected image datasets such that pairs of the selected image datasets which have different spatial intensity information between datasets within a respective pair, are assigned respective colours which have a different colour difference measure; and, f) combining a number of the selected image datasets together to form an output colour image dataset for the formation of a colour image such that each pixel of the colour image takes on a colour according to the relative intensities and colours of the said number of selected image datasets so that if the pixel intensity of one dataset is greater than the sum of the pixel intensities for all the other selected datasets, the output colour in the respective part of the image will match the colour assigned in step (e) to that image dataset.