1. A method for estimating a white point, comprising: displaying a plurality of grey patches on a display screen of a display device, wherein each patch is associated with an index for estimating a color temperature of the white point; applying a divided white point chromaticity axis to provide a constant luminance and a variable chromaticity for each patch; requesting that a user select one of the plurality of grey patches having a neutral grey color; adjusting the indices of the displayed grey patches according to the user selection; and iterating the steps of displaying gray patches and requesting user selection to converge to a grey patch where the estimated white point is the most neutral grey point.