1. A method of identifying motion within a field of view, the method comprising the steps of: capturing at least two sequential images within the field of view, each of the images including a respective array of pixel color values; calculating an array of difference values between corresponding ones of the pixel color values in the sequential images; providing a sensitivity region map corresponding to the field of view, the sensitivity region map including a plurality of regions having different threshold values; and determining a presence of motion by comparing the difference values to corresponding ones of the threshold values, the determining step including determining a presence of motion by comparing the difference values corresponding to one of the regions to a selected said threshold value of the region.