Patent ID: 7400355

Claim:
An image pickup apparatus, comprising: a solid-state image pickup device having high-sensitivity pixels and low-sensitivity pixels, a photometric characteristic of an output of the high-sensitivity pixels being different from that of the low-sensitivity pixels, wherein the high-sensitivity pixels have a first high-sensitivity exposure value ran e in which the function before becoming saturated and a second high-sensitivity exposure value range in which they function before becoming saturated and no exposure value in the first hi-sensitivity exposure value range overlaps with an exposure value in the second high-sensitivity exposure value range, the low-sensitivity pixels have a first low-sensitivity exposure value range in which they function before becoming saturated and a second low-sensitivity exposure value ran e in which the function before becoming saturated and no exposure value in the first low-sensitivity exposure value range overlaps with an exposure value in the second low-sensitivity exposure value range, the exposure value at which the low-sensitivity pixels be in to function in the first low-sensitivity exposure value range coincides with the exposure value at which the high-sensitivity pixels become saturated in the first high-sensitivity exposure value range, and the exposure value at which the low-sensitivity pixels begin to function in the second low-sensitivity exposure value range coincides with the exposure value at which the high-sensitivity pixels become saturated in the second high-sensitivity exposure value range; control means for (i) calculating an exposure value based on values of signal detected by said high-sensitivity pixels operating in the first high-sensitivity exposure value range and values of signal detected by said low-sensitivity pixels operating in the first low-sensitivity exposure value range, which are output from said solid-state image pickup device in a first single instance of photometry, and (ii) when a correct exposure value cannot be obtained in the first single instance of photometry due to saturation of both the high-sensitivity pixels and the low-sensitivity pixels, calculating an exposure value based on values of signal detected by said high-sensitivity pixels operating in the second high-sensitivity exposure value range and values of signal detected by said low-sensitivity pixels operating in the second low-sensitivity exposure value range which are output from said solid-state image pickup device in a second subsequent single instance of photometry, where during each of the first and second instance of photometry, aperture and electronic shutter speed are not changed; and signal processing means for reading data of an image picked up by said solid-state image pickup device and processing according to the calculated exposure value.