Patent ID: 7911506

Claim:
An image sensing apparatus comprising: an image sensor which converts an optical image of an object into an electrical signal; a first amplifier which amplifies the electrical signal by a first gain; a second amplifier which amplifies, by a second gain, the electrical signal amplified by said first amplifier, the second gain being changeable in finer steps than the first gain; and a control unit which sets a third gain based on brightness of the object, and adjusts the first gain and the second gain so that a sum of the first gain and the second gain equals the third gain, and adjusts the second gain so that a part of the second gain that cannot be adjusted by the first gain is adjusted by the second gain, wherein said control unit adjusts the distribution between the first gain and the second gain in a case where the brightness change of the object does not go beyond a preset range of a brightness difference and a predetermined period of time has passed since the brightness change is last determined, otherwise and said control unit adjusts the second gain without adjusting the first gain.