We measure it in our tests, and manufacturers like to emphasize it. Peak brightness is important, yes, but how important? When is your TV bright enough? And should you pay attention to certain things when buying a new TV?
Too much (peak) brightness?
We occasionally see a comment that screens are becoming too bright. Will we soon have to look at the screen with sunglasses? You can put that fear aside. An average television today may deliver 500 CD/m², better mid-range televisions can achieve 1,000-1,500 CD/m², and top models can achieve 2,000 CD/m². These differences seem large, especially compared to older devices that struggle to achieve 300 cd/m².
But appearances can be deceiving because our perception of clarity is not linear but logarithmic. This means that the smallest difference we can perceive between two stimuli is proportional to the size of the original stimulus. In concrete terms, we see differences much more quickly in dark than bright nuances. Also, we do not see a 1000 cd/m² screen as twice as bright as a 500 cd/m² screen.
Moreover, those figures pale in comparison to what we see around us every day. The fluorescent lamps in an average office reach 6,000 cd/m², asphalt on a sunny day 2,100 cd/m², and a colorful flower in the sun can even reach 15,000 cd/m². Since we don’t always walk around with sunglasses in everyday life, they are unnecessary for your TV. However, there are a few factors you should take into account, namely whether you watch HDR or SDR and the viewing environment.
SDR versus HDR
In SDR images, the brightness of the overall picture is adjusted based on the maximum brightness setting of the screen. In other words, the higher the peak brightness of your TV, the brighter the SDR images will be. This is important if you are viewing in a lot of ambient light (see below). It must be said that a TV in SDR rarely uses its full peak brightness. This is only used for HDR.
With HDR, peak brightness also has a substantial impact on image quality. In HDR (specifically HDR10, HDR10+, and Dolby Vision), the brightness of each pixel in the source video is fixed and can go up to 4,000 or even 10,000 cd/m². If a particular pixel in the image is recorded as 100 cd/m², then it should be displayed as 100 cd/m² on all TVs, regardless of the peak brightness of the TV.
However, the TV performs tone mapping for pixels that are brighter than what the TV can display. It adjusts the range of the brightest pixels based on its maximum brightness. For example, a screen with a peak brightness of 500 nits will display pixels that go up to 100 nits unchanged, but it will darken any pixels between 101 and 4,000 nits slightly so that they fit into its range of 101 to 500 nits.
A TV that can reach 2,000 nits peak brightness may only need to tone map from 500 nits. The difference between those two TVs is, therefore, huge. In HDR images that go up to 500 nits, the latter TV can display them unchanged, while the former even makes that image considerably darker because it does tone mapping from 100 nits. In addition, the second TV can also display much brighter images better. It shows a 4,000 nits accent somewhere on the screen as 2,000 nits, while the first TV must reduce that to 500 nits.
Viewing the environment, the impact of ambient light
Do you watch in a completely darkened room, like some movie buffs? Are you looking in some dim ambient light? Or do you look into the room with a lot of light during the day? That makes a difference, because our perception is relative.
This is very pronounced with SDR images. As mentioned, a TV scales SDR images based on maximum brightness. For example, if you look at (slight) darkening, that very bright image can still be stressful for your eyes. In that case, you should reduce the maximum brightness a bit or, better yet, activate the light sensor. If you watch in a lot of ambient light, a TV with high peak brightness is essential for SDR. The brighter images ensure that the image remains lively and intense and that you are less bothered by reflections.
With HDR, the impact of the ambient light is less pronounced precisely because the image’s brightness is fixed in the video file, and the maximum brightness of your screen is only used in small accents. The average brightness of most HDR images means that they are still delightful when viewed in darkened conditions. Those small light accents are very bright, which adds to the realism. If there is a lot of ambient light, you will benefit from a TV with high peak brightness, also in HDR. The image retains the desired intensity better because it has to tone map less strongly. You can also make the picture a little brighter via the settings to stand out against the ambient light.
Image technology and clarity
Not all TVs can deliver the same peak brightness. Unfortunately, manufacturers do not provide precise figures in the specifications you can rely on. That makes it very difficult to compare TVs in that area, especially between brands. We will give you several rules of thumb.
- Within a brand, you can generally expect that peak brightness will increase as you go higher in the lineup (and therefore higher in price).
- With most TVs, you typically only reach peak brightness on a minor part of the screen (we give figures for a 10% window). On a completely white screen, the peak gets lower and lower. Only on screens that do not have a very high peak brightness anyway, the result is the same on a small part or the entire screen.
For a long time, there was little distinction in peak brightness with OLED screens, but that has changed in recent years.
- Standard OLED TVs (think the LG C3, Philips OLED808 or Sony A80L) deliver a peak brightness of 700-800 cd/m² (10% window). On a completely white screen they achieve 150-180 cd/m².
- OLED TVs with microlens array technology (LG G3, Philips OLED908 and Panasonic MZ2000) are considerably brighter. They go up to 1,500 cd/m² (10% window) and achieve 220-240 cd/m² on the completely white screen.
- QD-OLED-tv’s (Samsung QN9xC, Sony A95L) halen tot 1.400 cd/m² en 270 cd/m².
- Both OLED with MLA and QD-OLED promise to be even brighter in 2024
With LCD TVs the results are much further apart. Performance is partly linked to the type of backlight.
- Entry-level models often barely reach 300 cd/m² and cannot show real HDR images.
- For example, mid-range Edge LED and Direct LED models (Philips PU8808 and Samsung Q7xC) perform between 400 and 600 cd/m².
- With Full Array Local Dimming devices (Samsung QN90C, Sony X95L, Hisense U79KQ, TCL C845) you get the best contrast and peak brightness, but there are major differences. Results range from 600 to 2,000 cd/m². These devices achieve between 500 and 900 cd/m² on a completely white screen.
As with many image quality-related matters, the settings of your TV have an impact on the result. Here we give you some tips that can have an effect on the (peak) brightness, but keep in mind that you ultimately determine what a comfortable image is to look at.
- Picture preset: We always test TVs in Filmmaker Mode or Film/Cinema mode for natural color reproduction. However, other picture modes can be a bit brighter. For example, the color temperature is cooler (tends more toward blue), and the TV can produce more light because the settings make the image brighter. In general, we recommend Filmmaker Mode (or similar), but if you mainly watch in a lot of ambient light, Standard or even Vivid may be a better choice.
- Light sensor: Almost all TVs have a light sensor. It measures the amount of light in the room and adjusts the maximum brightness of the image accordingly. If the circumstances you watch TV are very variable, leave it on. If you consider the same circumstances, out is often the better choice.
- Brightness: You can adjust the screen’s maximum brightness in the menus. Only do this for SDR! In HDR, you will notice that this setting is maximum, which is required because of how HDR works. This is often the first item in the image menu, but unfortunately, it hides behind different names. Samsung, Sony, and TCL use ‘Brightness’; at LG, you will find ‘Panel brightness’ and ‘OLED pixel brightness’; at Panasonic, it is ‘Illuminance’ or ‘Backlight’, and at Philips ‘Contrast Backlight’. OLED TVs often also have a ‘Light Boost’ to activate for more brightness.
- Local dimming: With LCD TVs with a Full Array Local Dimming backlight, you can often set different levels of local dimming. Just like for Brightness, you only adjust this for SDR! The highest setting gives slightly more peak brightness, but you may risk halos or zone boundaries.
Tips when buying a new TV
How do you use all this knowledge to determine the right purchase?
- Because no manufacturer provides concrete figures, reviews are your only source of information for TVs’ (peak) brightness. So inform yourself!
- The peak brightness of newer models is often better. That is not a hard rule, but sometimes there are clear jumps.
- If you don’t care about HDR, or if you only watch SDR (still a huge part of the offer), then peak brightness is much less important. Moreover, peak brightness is unimportant if you mainly view in subdued light. If you watch in a lot of light, choose a model with sufficient brightness (500 cd/m²).
- If you want to enjoy HDR, choose a device that delivers at least 500 cd/m² peak brightness, preferably even more. OLED TVs and the better LCD models. The impact of HDR increases as the peak brightness increases (but remember that we don’t perceive light linearly; a TV that delivers twice the brightness is not as good).
- If you mainly watch in low ambient light, choose an OLED TV. It provides the best contrast and has excellent peak brightness for HDR.
- If you mainly watch in ambient light, choose an LCD TV, an OLED TV with MLA technology, or a QD-OLED TV. I prefer a model with as much peak brightness as your budget allows. Contrast is less important than brightness in a lot of ambient light.
- If you mainly watch films and TV series, an OLED TV is often the better choice.
- If you mainly watch sports, an LCD TV is often the better choice.