- Table of Contents
- Intro
- Test Methodology Coverage
- When It Matters
- Our Tests
- Additional Information
- Conclusion
- Comments
Contrast Ratio
How We Measure Contrast On Dozens Of TVs Each Year
- 80.0% Contrast
- 20.0% Native Contrast
Contrast is one of the most important aspects of picture quality, whether we're talking about a TV, projector, laptop, or even the phone in your pocket. But what is it, and how do we measure it? Simply put, the contrast ratio is the ratio between the luminance of the brightest white and the darkest black a display can produce. In the world of TVs, contrast is king. A higher contrast ratio means that a TV can display deeper blacks and brighter whites simultaneously, so in HDR, bright highlights stand out even in relatively dark scenes.
Test results
Test Methodology Coverage
This test methodology has been updated for our 1.9 test bench and is also valid for 1.10 and 1.11. TVs tested before 1.9 used a modified ANSI checkerboard pattern instead and were measured with the white level set as close to 100 nits as possible. When comparing our latest results with reviews tested with older methodology, the measured contrast is mostly comparable, but the scores aren't. Learn how our test benches and scoring system work.
| 1.6 | 1.7 | 1.8 | 1.9 | 1.10 | 1.11 | |
|---|---|---|---|---|---|---|
| Native Contrast | ❌ | ❌ | ❌ | ✅ | ✅ | ✅ |
| Contrast With Local Dimming | ❌ | ❌ | ❌ | ✅ | ✅ | ✅ |
When It Matters
Getting a TV with a high contrast ratio is mainly noticeable if you're in a dark room. If you're watching a movie at night and there's a dark scene, is the image almost as dark as the rest of the room, or does it look gray? If it looks black, it has a high contrast ratio, but if it looks gray, it means it has a low contrast ratio. However, in bright rooms, the difference in contrast isn't as obvious, as bright lights reflecting off the screen increase the brightness of blacks. The screen's finish and anti-reflective coating have a greater impact on perceived contrast if you're in a bright room.
Our Tests
Although it's one of the most important aspects of picture quality, measuring contrast is one of the easiest tests we perform. We start by putting the TV into its post-calibration settings. Using our custom-designed real-scene test image, we start by adjusting the backlight so that the white area in the center of the cave is as close as possible to 200 cd/m2. This is the white luminance measurement used for our contrast calculation. We chose this value for two reasons. First, it's dim enough that any TV on the market can achieve it, which is important for comparable results. Second, it's representative of a brightness level used in a moderately-lit room.
Next, we take measurements of the light output on the four corners of the scene and one measurement to the right of the cave entrance. We take the average of these five measurements, which gives us the black luminance level for our contrast measurements. Finally, we divide the white luminance by the black luminance to determine the contrast ratio. We run this test twice to measure the native contrast of the panel and the best it can do with local dimming enabled.
Native Contrast
The native contrast measures the contrast ratio without any image processing settings enabled, like local dimming. Since it's a ratio, there's no unit for contrast. Instead, the norm is to express the number as 'X:1,' with 'X' being how many times brighter white is than black. For example, a 4000:1 contrast ratio would mean that the television emits white that's four thousand times brighter than its black. The higher the contrast ratio, the deeper the blacks, and the better the picture will look.
Contrast With Local Dimming
We then repeat the same process with local dimming enabled (if the TV has it). Our first step in this case is to determine the best local dimming setting. No local dimming feature is perfect, and in some rare cases, like the LG QNED80 2023, the local dimming feature is so bad that the best setting is to deactivate it completely.
Once we've determined the best local dimming setting, we repeat the same test as above, but this time with local dimming enabled and set to the best setting we previously selected.
Additional Information
Differences in Panel Technology
The type of panel used in a TV significantly impacts the final contrast measurement. If you plan on mainly watching in a dark room, OLED displays are the best choice, as they deliver the deepest blacks without any blooming around bright highlights. After OLEDs, TVs with VA panels tend to deliver the deepest blacks, and IPS/ADS are the worst performers. However, this isn't as universally true as it used to be a few years ago. With the advent of Mini LED backlights with thousands of dimming zones, IPS and ADS panels are closing that gap, with some TVs like the Samsung QN85A QLED delivering deep blacks similar to VA panels.
How To Get The Best Results
A couple of settings that can improve the contrast ratio, with the most important being local dimming. However, changing each of these settings can also affect picture quality, so there's a trade-off between improving the contrast and having the best picture quality available. Also, contrast may vary between units of LED TVs a bit; this means that the unit you buy may have a slightly higher or lower contrast ratio than the one we tested, even if the model is the same.
Related Settings
- Local Dimming: Dims the backlight behind darker portions of the screen. It improves the contrast most of the time and is worth using if it performs well. However, it can introduce issues like blooming around bright objects in dark scenes, and when done poorly, it can dim the entire image.
- Contrast: The contrast setting on most TVs increases the luminosity of the brightest whites. This could improve the contrast, but it usually negatively affects image quality.
- Black Level: Sometimes called 'Brightness' by some brands. Similar to the contrast setting, the brightness setting makes blacks darker when you decrease it. Once again, it can affect image quality, and we don't recommend using it, but it's up to you. However, some TVs may call their backlight setting 'Brightness,' and this doesn't affect the contrast ratio; it just makes the entire screen brighter. If that's the case, the brightness setting to change the black level may be called 'Black Level.'
- Dynamic Contrast: Uses software to process the blacks and make them darker. Unfortunately, this removes detail from the image and may not be worth using.
- Gamma: Gamma doesn't control the depth of black level, but it does control the amount of detail you see in dark portions of an image. If you find it difficult to make out detail in dark images, consider increasing the gamma. Check out our discussion of gamma in more detail.
Conclusion
The contrast ratio of a TV is one of the most important factors in picture quality. The higher the contrast, the better, as it improves picture quality in dark scenes. If your TV has a low contrast ratio, blacks look gray in a dark room, and bright highlights won't stand out well. A high contrast ratio is most noticeable when viewing content in dark rooms, but there's less of a noticeable difference in well-lit rooms.