An imaging section includes a radiation source that emits radiation, a detecting panel for detecting the radiation, and a rotating section for integrally rotating the radiation source and the detecting panel about a rotating axis. The radiation source and the detecting panel face each other with the rotating axis that passes though a predetermined position interposed therebetween. The imaging section sequentially images a subject placed at the predetermined position while rotating the radiation source and the detecting panel about the rotating axis, and image signals are read out for each imaging operation. A control section refers to a necessary readout region set by a setting section and controls a readout switching means such that image signals recorded in detection pixels within the necessary readout region are read out by a normal readout section, and image signals recorded in other detection pixels are read out by a high speed readout section.