To provide an imaging apparatus capable of adjusting the luminous quantity independently of an aperture.

When a user uses an operation section 51 to carry out photographing preparation operations, a data ratio controller 63 allows a digital signal processing section 57 to integrate a luminance signal of a low sensitivity image signal outputted from a slave photosensitive section 43 thereby detecting an incident luminous quantity, and calculates an optimum data ratio between outputs of a master photosensitive section and a slave photosensitive section in response to the detected incident luminous quantity. The data ratio controller 63 updates a data ratio setting value and thereafter allows the digital signal processing section 57 to carry out image processing according to the data ratio after being updated and allows an image display LCD 23 to display the processed image.