A software should be developing for testing the visibility and contrast effects of different objects. This test software has to show two objects e.g. two circles with different sizes but the same grayscale. Then a star or a polygon or a circle has to be visualized with the same size or with the same shape with different luminance values for different background luminance. The observer has to determine the luminance of the objects. The test results will be saved in a database. Then these data have to be analysed, depending on the size of the circle/ polygon/ star area or their perimeter.