1. Method for converting input image data (V in ) into output image data ({tilde over (V)} 1 , V out ) wherein the input image data (V in ) is split into at least two signals, a first signal (V RC ) comprising regional contrast data and a second signal (V D ) comprising detail data, the dynamic range of at least the first signal is stretched to provide a stretched first signal ({tilde over (V)} RC ), wherein the dynamic range of the first signal is stretched to a higher degree than applied to the second signal, and the stretched first ({tilde over (V)} RC ) and second ({tilde over (V)} D ) signals are combined in an output signal ({tilde over (V)} 1 ).