- 50.0%Real Scene Peak Brightness
- 5.0%Peak 2% Window
- 12.5%Peak 10% Window
- 15.0%Peak 25% Window
- 12.5%Peak 50% Window
- 5.0%Peak 100% Window
SDR peak brightness, as the name suggests, is simply a measurement of the peak luminance of a TV when displaying content mastered in SDR. For these tests, we use a luminance meter to measure the brightness of a few white rectangles in SDR, each covering different sizes on the screen. We also take a real scene measurement using a video that we created. The measurements are in cd/m², also known as 'nits.'
Test results
Test Methodology Coverage
The actual method we use to measure SDR brightness hasn't changed much since it was first introduced in TV 1.0 way back in 2015, but the way we interpret that data has. TVs have gotten a lot brighter over the years, so we've adjusted our scoring multiple times over the years, most recently as part of our massive TV 2.0 update. With TV 2.0, we also removed the scores for the sustained brightness test, adjusting the weights of the other tests to look only at the peak brightness. This means that if you're comparing TVs that haven't been tested with the same methodology, it's safe to compare the actual measurements but not the scores. Learn how our test benches and scoring system work.
| 1.6 | 1.7 | 1.8 | 1.9 | 1.10 | 1.11 | 2.0 | |
|---|---|---|---|---|---|---|---|
| Peak Brightness Measurements | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
| Scores | ❌ | ❌ | ❌ | ❌ | ❌ | ❌ | ✅ |
When It Matters
Brightness matters in any situation in which you want the picture, or part of the picture, to get really bright. Usually, this applies to one of two scenarios:
- Watching TV in a bright room. If the picture is too dim in a bright room, especially with sunlight or bright lights opposite the TV, it can be difficult, or even impossible, to see the screen properly. A TV with high peak brightness makes it easy to overcome glare by simply increasing the brightness. Keep in mind, though, that if you want to place your TV in a well-lit room, it's also important to get a TV with good reflection handling.
- Watching HDR video. There are several HDR formats that allow for brighter and more vivid colors, so even if a TV supports one of these formats, it's even more important to get a bright TV for a true HDR experience. This allows highlights to pop the way they're supposed to. However, we don't test HDR peak brightness the same way we measure SDR peak brightness. Learn more about our HDR Peak Brightness Tests.
Our Tests
Our testing for SDR brightness is fairly straightforward. The TV is placed in a dark room and allowed to warm up. We set the TV to its most accurate settings, including a full calibration if it supports it, but with the brightness setting at max. We connect a PC to the TV over HDMI and use it to display the test slides and video. All of our measurements are taken using a Colorimetry Research CR-100 colorimeter that's been properly calibrated to the display using a CR-250 spectroradiometer. This ensures that the measurements are accurate to the specific display we're measuring. We also spot-check measurements when needed with a Konica Minolta LS-100, but the final posted numbers are always from the CR-100.
We measure peak brightness with six separate test patterns. We measure five different window scenes, which represent various types of content from 2% to 100% full white. Finally, we use a real scene video test to measure brightness with real content. Across all six tests, we measure both the instantaneous peak brightness as well as the brightness a TV can sustain over time; however, as of TV 2.0, the sustained brightness is no longer scored. The sustained brightness measurements are also used to calculate the TV's automatic brightness limiter, or ABL.
SDR Real Scene Brightness
The SDR Real Scene Peak Brightness test is most representative of real-world usage. Using a video clip defeats any TV's built-in pattern detectors that might look for fixed static windows, as well as eliminating any static dimming that some TVs like OLEDs use to avoid burn-in. This gives you the closest results possible to what you'll experience in the real world with real content.
A result of at least 500 cd/m2 is good for pretty much any viewing environment. This will ensure your TV is bright enough to overcome glare during the day. Of course, if you're in a light-controlled room with blinds and curtains, or watching at night, then you'll probably find this too bright. Many TVs now feature built-in ambient light sensors that adjust the peak brightness of the TV to match your viewing conditions, so you don't have to worry about this.
To run this test, we set up the TV using the method described in the previous section, making sure to let it warm up properly before we take our measurements. With a PC connected directly to the TV, we play the video file on a loop. Using our CR-100 colorimeter, we place it on the lamp in the top-left of the video and follow it as it moves across the screen. We repeat this process at least nine times and take the maximum non-outlier measurement.
SDR Peak Window
Our peak window tests measure the maximum brightness of a white rectangle centered on the screen with a black background. There are multiple tests, and we refer to each test by the percentage of the screen the rectangle covers. This provides an idea of how bright a small highlight—the sun, a distant explosion, etc.—might look on-screen, but the larger areas can also represent very bright areas, like if you're watching something with a bright sky.
We use the same setup as the real scene test and measure the brightness immediately after the white square appears on-screen. This is because the TV is at its brightest at this point. We repeat the test with a 10%, 25%, 50%, and 100% white slide. Each of these slides represents different types of content you might encounter.
While it may be tempting to just look at the brightest measurement or the 100% slide, these don't usually represent the majority of content or how bright a TV will appear to you most of the time. To give a few examples, a 2% slide represents the darkest scenes you'll find, like a dark star field or the infamous Game of Thrones episode, "Long Night." These are generally very rare. Dim scenes closer to 10% are far more common, and the vast majority of regular content behaves closer to a 25% slide. Most sports, on the other hand, fall in the 50-100% range, so if you're a sports fan, you should pay more attention to those measurements.
SDR Sustained Window
We measure the SDR sustained window with the same test images as the SDR peak window, but the only difference is that we test for brightness after the window has been displayed for a few seconds. This allows the TV to 'stabilize' its brightness and is more representative of content with bright areas that stay on for an extended period, like on a hockey broadcast.
Automatic Brightness Limiter
TVs use algorithms to limit how bright the screen gets, especially with large areas, like in our 100% peak window test. It's done to prevent the entire screen from getting too bright and damaging internal electronics. What this essentially means is small areas get brighter than large areas, and we want to know just how much difference there is between the two. Our Automatic Brightness Limiter (ABL) coefficient variant calculates the difference in brightness between the sustained windows tests after normalizing for noticeable differences with the Perceptual Quantizer (PQ) EOTF. This means we only calculate the noticeable differences we can see when watching TV.
A TV with an ABL of 0 means the brightness doesn't change across different content. A high ABL is usually found on OLEDs, as large areas are noticeably less bright on those TVs. Also, it's possible for small highlights to be less bright than larger areas because of frame dimming on some TVs, as seen on the Vizio M7 Series Quantum 2020; in this case, the ABL is also high. ABL isn't something you should worry about too much if you just watch SDR content, as most TVs can maintain a high brightness level in SDR without any ABL.
Unfortunately, there's no way to control the ABL. Some TVs dim less than others do, though. If you watch content with large areas of bright colors, like hockey or brightly colored cartoons, you should look for a model that doesn't have too much of a decrease in brightness between the 25% window test and the 100% window test. Some TVs allow you to disable ABL from the service menu, but we don't recommend doing this, as ABL is designed as a protection mechanism for the TV. Disabling ABL could cause your TV to overheat.
Additional Information
Linearizing Luminosity
For the ABL calculation to be significant, it should correspond to the way we perceive different luminosity levels. The eye is much more sensitive to small changes in luminosity in a dark environment than in a bright one. Although the measured change in luminosity may be the same, the brighter source is better because we don't notice the change in brightness as much. Essentially, if a screen goes from 25cd/m² to 20 cd/m², it's more noticeable than a screen going from 100 cd/m² to 95 cd/m². This linearization is done with the PQ EOTF, as you can see below.
PQ is a function that relates luminosity with noticeable differences in brightness. When the PQ curve is divided into 4096 segments (12-bit), there are smaller steps that relate to the change in brightness; the horizontal dotted lines represent each step, and as you can see, the first step in each segment represents a higher change than the last segment. We use this to linearize all of our luminosity measurements for this test, ensuring the ABL best represents what's seen.
How To Get The Best Results
- Backlight/Brightness/OLED Light: These settings are what increase the luminosity. The majority of LED TVs call it Backlight, but Samsung and Sony call it Brightness. On OLEDs, it's usually called OLED Light, but the Vizio OLED 2020 has a Luminance setting. Whatever they're called, these settings are meant to adjust the luminance and are the best settings to use to get the brightest image possible.
- Local Dimming: Most LED TVs support a feature called local dimming, which adjusts the backlight behind darker parts of the image. This, in turn, allows them to shunt more power to the LEDs in brighter parts of the screen, increasing the overall brightness of those areas. Local dimming isn't always perfect, as it could cause blooming around bright objects. For that reason, you should choose the local dimming setting that gets you the look you like the best. This may mean getting the brightest highlights of which your TV is capable, or it might mean settling for slightly dimmer highlights that come with less blooming. Learn more about local dimming.
- Contrast: The contrast setting increases the brightest white, which could help increase the overall luminosity. However, changing this setting also affects picture quality, so we don't recommend changing it for the most part.
- Brightness: Opposite of contrast, the brightness setting controls the black level, and on some TVs, the setting itself is called 'Black Level.' Decreasing it makes blacks darker, but that means you can easily lose details, so we don't recommend changing it.
- Gamma: Gamma affects the brightness of the overall scene but doesn't impact luminosity. In our testing, we want TVs to follow a gamma target of 2.2; anything higher results in a darker overall image, and anything lower means the image is brighter. In the wider industry, gamma 2.4 or the BT.1886 gamma function are increasingly popular, so you should try these out and see which one looks best to you.
- Eco Mode/Light sensor: Most TVs now have a built-in ambient light sensor to detect how much light is in the room and adjust the backlight accordingly. These sensors have improved greatly over the years, so if you find yourself constantly adjusting the brightness setting on your TV, look for the eco settings and try them out.
- At the end of the day, you're the one watching TV, so if you want to make the image brighter, do whatever it takes to make it look better for your viewing experience. These are just generalized recommendation settings, and they change between TVs.
Conclusion
A TV's brightness indicates how bright images can get on the screen. It matters most if you watch TV in a well-lit room, as you want your screen to get bright enough to combat glare; otherwise, it may be hard to see. We test for a TV's brightness to know exactly how bright it can get, but also to see if it remains a consistent brightness level across different content. If you watch TV in dark rooms, then brightness shouldn't be something to worry about.
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Comments
Our TV Picture Quality Tests: SDR Peak Brightness: Main Discussion
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- 21010
Hey RTINGS guys, you’ve updated the HDR video a few years back, right? Any plans to update the SDR video, or is it staying as is?
Hi James_92,
Thanks for reaching out with your question!
That’s correct, we’ve changed our HDR Brightness test by adding three HDR real scene tests in Test Bench 1.7 back in 2022. As of now, we don’t plan on reworking our current SDR Brightness test, though we may do so if a need to arises in the future.
Out of curiosity, what improvements or changes do you think our SDR Brightness test could benefit from?
Looking forward to hearing from you
- 21010
Hey RTINGS guys, you’ve updated the HDR video a few years back, right? Any plans to update the SDR video, or is it staying as is?