Abstract: A method for correcting image data, in particular for colour correction and cross-talk reduction of image data obtained by an image sensor comprising image pixels (R, G, B) and non-image pixels (F), the image pixels (R,G,B) being overlaid with a colour filter array (CFA) and having a different spectral sensitivity than the non-image pixels, comprises determining a set of colour components (rold, gold, bold) for the image pixels (R,G,B) based on raw image data (rraw, graw, braw) read only from the image pixels (R,G,B) of the image sensor (10); correcting the set of colour components of non-direct neighbours of the non-image pixels (F) by means of a first colour correction matrix (CCM1); and correcting the set of colour components of direct neighbours of the non-image pixels by means of a second colour correction matrix (CCM2) different from the first colour correction matrix. An image sensor (10) and an auto-focus camera using same are also disclosed.