A digital camera is disclosed to reduce shutter lag and improved accuracy in exposure. The digital camera includes an image pickup lens optical system, an iris, an image pickup device, a hold/gain control circuit, a luminance level detector, an exposure control circuit, a device control circuit and so forth. The exposure control circuit discriminates based on a luminance level supplied thereto from the luminance level detector whether or not appropriate exposure is performed. Then, based on a result of the discrimination, the exposure control circuit arithmetically operates three values of the numerical aperture of the iris, the shutter speed of an electronic shutter of the image pickup device and the gain of the hold/gain control circuit which are necessary to perform appropriate exposure. The exposure control circuit arithmetically operates iris control data, electronic shutter control data and gain control data necessary for the arithmetically operated exposure amounts to be individually reflected on the iris, the electronic shutter of the image pickup device and the hold/gain control circuit.