The Processing of high-dynamic-range (HDR) images is embodied by a lot of algorithms. This paper takes notice of one of these algorithms which is presented using the iCAM06. iCAM06 is capable of making color appearance predictions of HDR images based on CIECAM02 color predictions and incorporating spatial process models in the human visual system (HVS) for contrast enhancement. The effect of user controllable factors of iCAM06 was investigated and the best factor which corresponds with Breneman's corresponding color data sets was found. A suggested model improves color matching predictions for the corresponding color data set in Breneman's experiment.