A radiation apparatus conducts a subtraction imaging process where a holder 25 begins to shift when a radiation output ends relative to a first radiation in association with the subtraction imaging and then, once the filter is switched by shifting the holder 25 and when switching of the filter is actually measured, the X-ray tube outputs the radiation in association with a second imaging. With this structure, dual filter is not required to be switched and the imaging can be conducted immediately after an operator so instructs regardless the dual filter phase. The second imaging can be performed immediately after confirming the dual filter is switched in fact.