Abstract: A data acquisition circuit for receiving an analog input signal having a magnitude representing light intensity detected by a sequentially accessed, linear array of photocells of a line scan camera and providing digital data signals for use by a computer, the circuit including an analog-to-digital converter to convert said analog input signal to a stream of digital intensity signals, an offset memory storing offset correction values for respective photocells, a gain memory storing gain correction values for respective photocells, an adder connected to add or subtract the digital intensity signal for a given photocell to the offset correction value for that photocell and provide an offset-corrected digital signal, a multiplier connected to multiply the offset-corrected digital signal for a given photocell times the gain correction value for that photocell to provide a calibrated digital signal. Also disclosed are: comparing, on a photocell-by-photocell (i.e.