In all CRT and LCD devices, the black level is referred to the brightness and the adjustment of the black level is very important to get the perfect picture in the display of a monitor or TV. The black level makes the picture well balanced and clear. The black level in the Display device can be adjusted manually in order to obtain the perfect setting. While setting the black level, the first strip is the darkest and the following strips become brighter and a lighter shade of grey. For Black level adjustment, you should use the left most strip.