1 24 bit version - very smooth

2 16 bit version - slightly banded

3 8 bit version - more bands

4 4 bit version - very basic

You can tell your current display setting from the above icons. They are the same image but saved with different color resolution settings. Of course if you are viewing this with your display set to 16 bit color you will not be able to tell the difference between images 1 and 2. If your display is set for 8 bit color you will not be able to tell the difference between images 1, 2, and 3.