Systems and methods for focal spot motion detection and correction

The techniques disclosed may be used to detect and correct channel gain errors resulting from X-ray focal spot mis-alignment during the course of a scan. One benefit of the present invention relative to conventional techniques is that additional hardware is not required for detection of focal spot drift. Instead, the static mis-alignment of each blade is taken into account as part of estimating and correcting X-ray focal spot drift or mis-alignment. In this manner, the risk of image artefacts due to focal spot motion is reduced and the need for costly hardware solutions to detect focal spot motion is avoided.