A method is provided for converting a digital colour image to a digital colour image with improved colour distinction. This method improves the colour distinction in a colour image for an observer suffering from a colour-blindness. The method includes defining a number of main colour values of a received digital colour image, converting the main colour values to converted main colour values such that the converted main colour values are perceived as distinguishable from each other by a colour-blind observer, and rendering the digital colour image with the converted main colour values.