Should Screen Contrast Be Higher Than Brightness?
More than half of us feel our eyes become strained after spending too long looking at a computer monitor.
Too high a contrast between white and black colors on screen, on top of excessive amounts of bright light being emitted are both contributors to the early onset of eye fatigue as well as an overall reduction in picture quality.
Optimising display settings is crucial for those of us working from the computer all day or gaming for longer than is probably considered healthy!
Whilst comparing settings on different screens in different ambient light levels is arguably arbitrary, on balance across monitors we were able to test the optimal screen settings were achieved when contrast was set about 50% higher than brightness (i.e. if brightness was set at 40/100; contrast tended to be around 60/100).
Brightness and contrast are of course two independent variables of a screen setting however each are intrinsically linked to one another.
You can obtain the optimal balance of contrast vs brightness on your own monitor by following these 4 simple steps:
- turn the CONTRAST control to minimum
- the monitor will display a black picture
- adjust the BRIGHTNESS control to cause the black picture to be seen as true black
- adjust the CONTRAST control back up until your reach a brightness level you desire
This post considers the correct balance of contrast and brightness to produce the best picture and prevent eye fatigue. If you would like to learn whether a glossy or matte screen is the best design of monitor to protect your eyes, check out our glossy vs matte guide here.
Screen brightness vs Screen contrast
The brightness setting works by introducing a bias to the red, green and blue signals to control how bright a screen appears. In monitors this luminescence is measured in units of candela per meter squared or cd/m2.
Placing a blanket recommendation on what brightness setting is best set across all monitors is not possible. This is because optimal brightness levels will be determined by the ambient light levels that exist in your room.
In a room full of natural light the monitor brightness must be increased to be able to see the display correctly. Too low a low brightness setting on the other hand and the monitor will appear dull, thus requiring our eyes to work harder to adjust to the text on screen.
Instead the aim of adjusting the brightness setting should be to allow black picture content to be displayed as close as possible to true black on your monitor.
Contrast on the other hand is the ratio of luminance between the brightest white and the darkest black that can be produced by the monitor. When contrast is increased the whites get whiter and the dark areas become darker.
Optimal screen settings for brightness and contrast
As we’ve learned, it’s the ambient light level that makes it difficult to place a standard recommendation on what screen brightness and contrast setting you should go for.
If you game in a basement without windows for example, you’ve less to think about as the ambient light levels should stay consistent throughout the day. Set up the screen using the points 1-4 above and you shouldn’t need to think about touching these settings once again.
This is in stark contrast to a screen positioned next to a window that experiences the changing color and brightness of natural light each and every day.
To set the brightness levels alone the easiest way is to hold a sheet of paper next to your screen. You should adjust the brightness of your screen to mimic how bright the paper appears.
This works because a sunnier room will mean the paper is brighter, and hence your screen should be brighter. The opposite is true in low-lit rooms.
Many newer models of computer screens have ‘night mode’ where they will greatly reduce the brightness and contrast according to the system clock (which remains in tune with sunrise and sunsets appropriate to your geographic location).
Many apps and programs these days also offer “dark mode” where the background is a dark tone with light text. This makes for a more relaxed screen experience when there is little ambient light in a room or working environment.
If you’re so inclined and want to have a deep dive into calibrating your monitor to get the perfect balance of contrast and brightness, you can use this free DIY test. In it there are hints and pointers on how to address and fine tune screen sharpness, gamma calibration and viewing angle.
Setting your contrast or brightness values too high or low will result in your eyes straining and may cause your eyes to fatigue much faster. In the long-term, this is damaging to your eyes and should be avoided.
Setting your contrast higher may also cause extreme sharpness and distortion in the image which will also contribute to eye fatigue. It’s also important to have brightness settings configured properly: too bright and you’re staring into a spotlight, and too dark will cause your eyes to strain and struggle to find detail on-screen.
If you’ve just purchased a new monitor, experiment with the settings and try doing the tests mentioned above to find the most comfortable screen values, as the best working screen settings are different for everyone and for different environments.