An image pickup apparatus comprising: a plurality of pixels, each including a photoelectric conversion means for converting an optical signal from an object into an electrical signal, an amplification transistor for reading out the signal from said photoelectric conversion means and a reset transistor for resetting an input node of the amplification transistor; a plurality of output lines connected to the plurality of pixels; a control circuit configured to control (i) a read out, to the output lines, a pixel noise signal VN derived by resetting the input node of the amplification transistor, and (ii) a read out, to the output lines, a pixel signal VS containing a signal generated by the photoelectric conversion means and read by the amplification transistor; difference means for performing difference processing between the pixel noise signal and the pixel signal; characterized by detection means for detecting an image pickup condition by comparing either a level of the pixel signal VS with a first predetermined level VA or by comparing a level of the pixel noise signal VN with a second predetermined level VB; and correction means (15, 19) for performing correction of execution of difference processing in accordance with an output from said detection means, wherein said correction means is configured to either control said difference means not to perform difference operation and output the pixel signal VS, or convert a signal output from the difference means into a third predetermined level, in case the level of the pixel signal VS is detected by the detection means to be at the first predetermined level VA or more, or the level of the pixel noise signal VN is detected by the detection means to be at the second predetermined level VB or more. a plurality of pixels, each including a photoelectric conversion means for converting an optical signal from an object into an electrical signal, an amplification transistor for reading out the signal from said photoelectric conversion means and a reset transistor for resetting an input node of the amplification transistor; a plurality of output lines connected to the plurality of pixels; a control circuit configured to control (i) a read out, to the output lines, a pixel noise signal VN derived by resetting the input node of the amplification transistor, and (ii) a read out, to the output lines, a pixel signal VS containing a signal generated by the photoelectric conversion means and read by the amplification transistor; difference means for performing difference processing between the pixel noise signal and the pixel signal; characterized by detection means for detecting an image pickup condition by comparing either a level of the pixel signal VS with a first predetermined level VA or by comparing a level of the pixel noise signal VN with a second predetermined level VB; and correction means (15, 19) for performing correction of execution of difference processing in accordance with an output from said detection means, wherein said correction means is configured to either control said difference means not to perform difference operation and output the pixel signal VS, or convert a signal output from the difference means into a third predetermined level, in case the level of the pixel signal VS is detected by the detection means to be at the first predetermined level VA or more, or the level of the pixel noise signal VN is detected by the detection means to be at the second predetermined level VB or more.