1. A method of estimating scatter in an image, where radiation from a radiation source is transmitted through an object to be imaged and is incident on a detector at an inclined angle, comprising the steps of: explicitly modeling an effect of angular incidence of the radiation on a scatter signal, including deriving, using an empirically based correction which includes the effect of an angle of incidence of the radiation on the detector, an estimate of the scatter signal in image data derived from the incident radiation on the detector.