PC monitors: How to buy the best LCD computer monitor Monitor picture quality
Which? reviews of computer monitors include tests of 27 different aspects of picture quality, combined into a single rating. We also ask a panel of experts to provide an assessment of the overall quality of the picture.
This way, we can be confident that the Which? Best Buy computer monitors are the best monitors you can buy.
Viewing angle
Monitor viewing angle indicates how far you can move from the centre of the screen for the picture to still be visible. It’s measured in both horizontal and vertical planes, and generally wider viewing angles are better. Typical values for viewing angle are 140 degrees horizontal and 120 degrees vertical.
If you plan to use your monitor to watch TV and films or play games with others, you need to consider whether those sitting either side of you can enjoy what’s on screen. Which? monitor reviews include ratings for each monitor’s viewing angle.
Brightness
Monitor brightness is expressed as candelas per square meter (cd/m2). Most LCD monitors have a brightness level of 250cd/m2 or greater, which should be more than sufficient.
Be aware that monitor retailers may set the brightness level to maximum on in-store display models to make the screen look more impressive to potential customers.
Though high brightness can be alluring for video and gaming, it be uncomfortable for prolonged viewing, especially of text.
Contrast ratio
This term refers to the difference in light intensity between the brightest white and the darkest black that an LCD can produce.
Look for a contrast ratio of at least 400:1 or better, as colours can appear washed out on monitors with lower contrast ratios.
As there's no industry-standard measurement for contrast ratio, each manufacturer can base its quoted contrast ratios on different measurements. Therefore, use contrast ratio as a guide, and don't choose a monitor solely on the basis of a high contrast level.
Response time
Pixel response time is a measure of how long it takes for a pixel to change colour (measured in milliseconds).
Shorter response times (lower numbers) are generally better, as it reduces the likelihood of motion artifacts (ghosting) and blur in moving images. The fastest response times are generally of interest to those who want to use a computer monitor for the latest games.
As a guide, a basic monitor might have a response time of 8ms, while the best monitor might offer 2ms. Some monitor specifications might quote LCD response time in one or both of two ways:
- Rise-and-fall response time The time taken for a pixel to turn from black to white then back to black. This is an industry-standard measurement and therefore should be comparable between monitors from different manufacturers.
- Grey-to-grey response time Measures the time it takes for a pixel to change from one shade of grey to another. This measurement of response time is less clearly defined, so there may be differences in the way individual manufacturers measure and quote grey-to-grey response times.
Monitor adjustments
The majority of monitors can be tilted on their stands. More expensive monitors also let you adjust the height of the screen, which is important for being comfortable when sat at your computer for long periods of time, and avoiding neck problems.
Side-to-side swivelling makes a monitor easy to rotate to show to people sitting close by.
The least common type of physical monitor adjustment is a screen pivot, where the screen can rotate between landscape and portrait modes – ideal for viewing full-page documents or long web pages.
