1. A system for generating a three-dimensional model of an object, the system including: a portable hand-held imaging device including: a housing; a plurality of sensors attached to the housing; at least one electronic processing device coupled to the plurality of sensors, wherein the electronic processing device: determines from the plurality of sensors and whilst the imaging device is in at least two different poses relative to the object: range data indicative of a range of the object; thermal infrared data indicative of a thermal infrared image of the object; generates a three-dimensional model based at least partially upon the range data from the at least two different poses, wherein at least two thermal infrared images from different poses overlap so that the at least two images include an object surface part; and associates model data derived from the thermal infrared data from the at least two different poses with the three dimensional model to thereby provide a three dimensional thermal infrared model of the object by: selecting the object surface part; identifying the at least two thermal images from different poses including the selected object surface part; identifying at least one image pixel corresponding to the selected object surface part in each of the at least two thermal images; and, determining a confidence score associated with each image pixel; and determining the model data from a weighted sum of data associated with the identified image pixels, wherein the weighted sum is determined using the confidence scores for the identified image pixels.