1. A method for detection of on-ground or near-ground discrete objects having characteristic features from a data set characterising a search area, the method comprising the steps of: determining the characteristic features of a on-ground or near-ground object and the characteristic size of discriminatory elements of said on-ground or near-ground object; determining a slope analysis scale for the on-ground or near ground object and for the discriminatory elements; determining a suitable grid resolution with reference to the characteristic size of said discriminatory elements such that the grid provides sufficient sampling points within the scale of the discriminatory elements to permit identification of said discriminatory elements and thus identification of said on-ground or near ground object; and processing the data set to form a gridded data set comprising a regular grid having the determined grid resolution; and analysing said gridded data set to identify said on-ground or near-ground discrete objects within said search area.