A control method for a radiation image sensing apparatus including an image sensing area where a plurality of conversion elements are arranged and used in an image sensing operation of acquiring a radiation image corresponding to incidence of radiation, a detection element configured to detect radiation entering the image sensing area, and a readout unit, the method characterized by comprising:
- a first step of acquiring a correction signal read out from the detection element by the readout unit after an end of incidence of radiation in a first image sensing operation;
- a second step of reading out a detection signal from the detection element by the readout unit during the incidence of the radiation in a second image sensing operation performed next to the first step;
- and
- a third step of correcting the detection signal in accordance with a correction amount based on the correction signal, and detecting an incident radiation dose based on the corrected detection signal.