Image pickup apparatus including image pickup element having image pickup pixel and focus detection pixel and signal processing method

An image pickup apparatus comprising:

• an image pickup element including a reference region, a plurality of first image pickup pixel portions for an image formed by a light beam from an image pickup optical system and a plurality of second pixel portions for focus detection;
• a signal processor configured to perform a shading correction for a pixel signal from the image pickup element;
• wherein, in an output mode, the image pickup element generates and outputs a first pixel signal by combining signals from the plurality of first image pickup pixel portions, and generates and outputs a second pixel signal without combining a signal from the second pixel portions, and
• wherein, in the output mode, the signal processor performs a first correction for the first pixel signal and the second pixel signal using correction data based on a pixel signal from the reference region, and performs a second correction only for the second pixel signal using additional shading correction data different from the correction data in the first correction.

An image pickup apparatus comprising:

• an image pickup element including a reference region, a plurality of first image pickup pixel portions that perform a photoelectric conversion and a plurality of second pixel portions that are formed so that an opening region of a photoelectric conversion area corresponding to a microlens for the second pixel portion is smaller than an opening region of a photoelectric conversion area corresponding to a microlens for the first image pickup pixel portion;
• and
• a signal processor configured to perform a shading correction for a pixel signal from the image pickup element,
• wherein, in an output mode, the image pickup element generates and outputs a first pixel signal by combining signals from the plurality of first image pickup pixel portions, and generates and outputs a second pixel signal without combining a signal from the second pixel portions, and
• wherein, in the output mode, the first pixel signal is corrected using shading correction data based on a pixel signal from the reference region, and the second pixel signal is corrected using the shading correction data and additional shading correction data relating to a difference between the first and second pixel signals.