This article will help you understand contrast ratios and how they impact your viewing experience on various devices.
What Is a Contrast Ratio?
Contrast ratio is the measurement of the difference between a display’s maximum and minimum brightness; put another way, it’s the ratio between the brightest white and the darkest black. For example, a contrast ratio of 1,000:1 means that the brightest white image is 1,000 times brighter than the darkest black. Generally, a higher contrast ratio is better since a display with a 100,000:1 ratio can produce darker black levels and more saturated colors than one with a 1,000:1 rating, thus achieving a more natural-looking image. That said, a bigger number isn’t always better, as you need to take external lighting conditions into account the lighting conditions and the type of display into account.
What Is a Good Contrast Ratio?
As previously mentioned, a higher contrast ratio has its benefits but isn’t the only thing you should consider. For example, a projector with a lower contrast ratio could provide an optimal viewing experience if you’ll be using it in a room with a lot of ambient light. Contrast ratios can also vary significantly across different display types. While a transmissive digital projector may only have a contrast ratio of 200:1, many newer TVs are over 4,000:1. But even these figures don’t tell the whole story, as contrast ratios are dependent on the underlying technology and how they are measured.
Static vs Dynamic Contrast
When looking at a display’s contrast ratio, it’s important to understand the various ways in which they are measured. The actual ratio you see can be broken down into two different types: Static Contrast and Dynamic Contrast. Static Contrast, otherwise known as “native” or “onscreen,” is a ratio comparing the brightest and darkest shade a display system is capable of producing at the same time. Since this ratio reflects the results from when the panel was made, industry experts typically consider this a more accurate representation of a display’s capabilities. Dynamic Contrast offers a more theoretical range of a display’s contrast ratio, as it’s heavily dependent upon the screen’s underlying technology. Here, the range between the lightest areas of an all-white/light scene and the darkest areas of a black/dark scene is measured. The problem with dynamic contrast measurements is that they are typically dishonest, as you’re unlikely to experience such a wide contrast range in the same scene. On top of this, manufacturers can manipulate contrast to make a scene lighter or darker using a display’s backlighting and firmware.
How Is Contrast Ratio Measured?
Unfortunately, there is no standardized measurement of contrast ratio. Particularly in the TV market, manufacturers can essentially inflate their ratings due to a combination of measurement and unstated variables. That said, most contrast ratios are measured using one of two methods:
ANSI Contrast (Measures Static Contrast Ratio)
This method uses a checkerboard pattern test image of alternating black and white squares and measures the average white output divided by the average black output. Displays that measure with this method tend to register lower contrast ratios as ANSI contrast provides a more realistic measurement of the screen’s capability. However, since the test can include a room’s lighting conditions in its measurement, it needs to be performed in an ideal environment for the most accurate reading.
Full On/Off (Measures Dynamic Contrast Ratio)
This method measures an all-white screen with an all-black screen and reflects equal proportions of light from the display to the room and back. It’s the preferred method for many manufacturers, as it cancels out exterior lighting conditions and results in an ideal (and thus higher) contrast ratio. Unfortunately, dynamic contrast specs are often misleading since they can be inflated and don’t indicate much about how an average image’s contrast will look.
Choosing the Right Contrast Ratio
Since contrast specs can be misleading, it may take some effort to determine whether a display offers rich black levels and a natural-looking image. The eye test is the best tool at your disposal — if a display’s black levels look washed out and gray, its contrast ratio probably isn’t high enough. However, there are other ways to ensure you’re not being misled:
Look for vendors that publish ANSI contrast specs, as this is a more accurate reflection of the display’s true contrast range. Unfortunately, many companies don’t disclose these figures, as ANSI readings tend to be much lower than Full On/Off, and it’s simply a better marketing strategy for these companies to focus on the latter.Pay attention to backlighting technology. If you’re looking for a TV with a high contrast ratio, an OLED display will offer a better viewing experience than an LCD panel, as the OLED’s pixels don’t rely on a backlight and can display deeper blacks without a “blooming” effect.Stick to the same manufacturer when making comparisons. Since every company arrives at its contrast ratios through different means, comparing displays produced by the same manufacturer is an excellent way to get consistent figures.
