A technique for compensating for a retained image includes employing bimodal readout of alternating light and dark images. The bimodal readout technique results from reading either light or dark frames more rapidly, allowing additional time to be allocated to the X-ray exposures occurring prior to the light frames or to the other reading operation. The bimodal readout may be accomplished by a binning procedure by which scan lines are binned and read, typically during dark frame readout. The images acquired from reading the dark frames may then be used to compensate for a retained image artifacts present in the image derived from light frames.