A filter insertion/removal unit that is capable of removing and inserting a variable neutral density filter having a variable transmittance from and into the incident light path of object light to an imaging device unit is instructed to insert the variable neutral density filter, and a variable transmittance drive unit is instructed to lower the transmittance of the variable neutral density filter, both on the basis of detection of a transmittance lowering operation of an operating unit. Also, the variable transmittance drive unit is instructed to raise the transmittance of the variable neutral density filter, and the filter insertion/removal unit is instructed to remove the variable neutral density filter from the incident light path, both on the basis of detection of a transmittance raising operation of the operating unit.