Working long hours at the computer might generate headaches, eye strain, and fatigue, especially if you stay in front of the monitor during nighttime. Adjusting the monitor's light to the light in the room is very important, as large discrepancies between the two might affect your eyesight. The fullscreen color filter that PC Shades offers might be of help in this matter.
Packed inside a lightweight archive, PC Shades can place a colored veil across your entire desktop. The filter dims the screen light, which prevents eye irritation during the night, allowing you to look at the monitor without being blinded by its light.
By default, the color the application uses is blue, which is considered one of the most but you can change it to whatever you like. Furthermore, the screen brightness can be adjusted either using the '+' and '-' buttons in the main window or by pressing 'CTRL-L' (to make the screen lighter) or 'CTRL-D' (to make the screen darker). Unfortunately, these shortcuts only work when PC Shades is not minimized, which is quite annoying.
The 'Setting' menu is another way to change the color and adjust the brightness (the same can be done by clicking on the color box, and the '+' and '-' signs).
The only additional options in this menu are to configure PC Shades to launch at startup, and to rotate colors periodically. This latter feature instructs the application to randomly change the monitor's color after a specific time interval. Frankly, unless you want to turn your computer into a disco ball, there is no point in doing that, as switching to another color with a completely different hue and light exposure would only put extra strain on your eyes.
The idea behind PC shades is to protect your eyes when using the computer for extended periods. Nevertheless, the only thing that this application manages to do is color your entire monitor in whatever hue you want, without making any recommendations for daytime or nighttime, as users probably expect from such an application.
It can be used as a color filter for your monitor, but note that its settings are not quite well organized and further improvements are required. Moreover, it does not have the capability to automatically adjust the brightness of the screen as the day goes by and the light in the room changes, which would be an interesting feature.