1. A method for generating a radiance map, comprising: calculating mean difference curves f(z) for pixel values z by taking with a camera a sequence of n images with different exposures and calculating for each of n images a mean difference curve comprising mean difference values for each pixel value, and calculating a transformation curve T(y i ) from the mean difference curves by iteratively selecting pixel values y and the corresponding difference values from the mean difference curve, wherein starting from the maximum possible pixel value as the first pixel value, the next pixel value is chosen by subtracting the mean difference value f(y i ) for that first pixel value y i from that first pixel value according to the equation 
 y i+1 =y i −f ( y i ), where i=0,. .. , t and y 0 =2 t −1 for t bit images until minimum pixel value is achieved, taking a difference for the chosen pixel values with the powers of 2, so that 
 T ( y i )= y t−i −2 i , and transforming each of n exposure images to its corresponding radiance map by subtracting for each pixel of the exposure image the difference of the transformation curve.