A system for dosimetry includes a radiation source that provides a pulsed radiation beam to a treatment zone, and a thin sheet of scintillator disposed between the radiation source and skin of a subject in the treatment zone. A gated camera images the scintillator integrating light from the scintillator during multiple pulses of the radiation beam while excluding light received between pulses of the pulsed radiation beam; and an image capture and processing machine that receives images from the gated camera and performs additional corrections to provide a map of dose received by the subject.