- 1 Audio-/Video-Formats
- 2 Display terms
- 3 Features
- 4 Picture Inaccuracies
It can be hard to keep track of televisions with so many technical terms in use. This is why we made a list of all the technical terms we use. They are sorted alphabetically in their categories. If you’re missing a terms explanation, please let us know in the comment section at the bottom of the page. We will then add the term as soon as we can.
Dolby Vision is a dynamic HDR format. Dynamic means that the Tone-Mapping Curve can be adjusted scene by scene. In theory Dolby Vision supports a color depth of up to 12 Bit and can be mastered at a maximum luminance of up to 10,000 Nits.
HDR – High Dynamic Range
HDR is a format which contains metadata enabling a larger dynamic range (contrast) and a larger color gamut. It is often used as a generic term for the different HDR formats like HDR10, HDR10+ and Dolby Vision. Find more about HDR here.
HDR10 is a format with colors in the Rec 2020 color space and a 10 Bit color depth. HDR10 movies are usually mastered at a maximum luminance of 1000 Nits.
HLG – Hybrid Log Gamma
Hybrid Log Gamma is simplification to transmit and emit the SDR and HDR Signal. Both Signals are combined into one and therefore only one Signal has to be emitted by the live broadcaster. This reduces the amount of data that has to be sent by the broadcaster without causing any data losses. HLG is mainly used to process 4K content at 100 Hz without affecting the image quality.
SDR – Standard Dynamic Range
Standard Dynamic Range is used for “normal” videos without HDR, with a conventional dynamic range and gamma curve.
The color depth is measured in Bit. 8 Bit stands for 28 different values for each color channel. For TVs those are red, green and blue. By combining the 3 rgb channels 28*28*28=16.777.216 colors are possible. If the color depth isn’t high enough banding can occur. HDR10 or the dynamic HDR formats, like Dolby Vision, work with 10 or even 12 Bit.
The gamut is the amount of colors or color tones a screen can display. For HDR a wide color gamut is required.
Hertz is the derived SI-unit of frequency with 1Hz=1/s . When talking about TVs this means how many different pictures a TV can display in one second (=refresh rate). It usually is a fixed number and should not be confused with frames per second (fps). But there also are TVs with a VRR.
The Input Lag is the amount of time (latency) a TV or monitor needs until displaying the input signal on the screen. A low input lag is especially crucial for video games. If the input lag is below 20ms most people won’t notice it.
With most inputs being 30fps or less, a TV with a refresh rate of up to 120Hz can use interpolation to calculate the missing frames. This makes motion appear smoother yet it can also cause the Soap Opera Effect.
IPS – In Plane Switching
IPS is a type of LCD panel. The advantages of In Plane Switching are a usually short response time and a wide viewing angle. The black level and contrast ratio isn’t as good as with other types of displays though.
A Liquid Crystal Display (LCD) is a type of display, which uses said crystals to polarize the backlight resulting in the picture you see.
Motion Handling is the general term for how well a TV is displaying moving content.
A Nit is the SI unit of luminance: 1 nit = 1 cd/m2 meaning the luminous flux (or luminous power) per projected source area. Average and maximum luminance are the best way to compare the brightness of different displays.
The response time is the time it takes a pixel to change its color. Usually, the time a pixel needs to reach 80% of a full transition from one basic color (RGB) to another is measured. The response time is amongst the most important aspects for determining a TV’s motion handling. If the response time is too high it will be visible as motion blur.
VA – Vertical Alignment
VA is a type of LCD panel. Advantages of Vertical Alignment are deep blacks and a high native contrast ratio. The viewing angel on the other hand isn’t too great.
VESA is an abbreviation for the Video Electronics Standards Association. It is commonly used for their standard for the mounting interface: Flat Display Mounting Interface (FDMI). The two numbers of a VESA FDMI (e.g. 600 x 400) are the horizontal and vertical spacing between the screw threads.
VRR – Variable Refresh Rate
A TV supporting a variable refresh rate can adjust its frequency to the output frequency of a connected graphics card with the same feature. This not only reduces the input lag and improves a games motion handling, but it also prevents tearing.
Dithering is a technique used to display colors the TV normally couldn’t display. It is most commonly used to display a 10 Bit color depth with an 8 Bit display.
FRC – Frame Rate Control
Frame Rate Control is a certain type of dithering. With rapid cyclic switching between two different color tones a color tone in between the two is simulated.
PVR – Personal Video Recorder
With the PVR feature a TV can record the program onto a USB device like a HDD or Stick.
Artifact is a term used for picture inaccuracies/errors as a result of the TV’s hardware or picture processing.
Black Crush is the loss of detail in dark scenes. For example the TV cannot display shadows on very dark clothing or it crushes bright stars in the night sky.
The problem of banding is if you can notice steps in color tones in a gradient.
Blooming describes an unwanted glow around bright objects on a dark background. The reason for blooming is the backlight. Some televisions try to fight blooming with their local dimming algorithm. The edges of bright objects are dimmed down to do so. This can result in “reverse blooming” though.
Clouding, or flashlighting, is used for bright spots (clouds) resulting by the backlight, local dimming feature or the resulting change in temperature. Clouding is most common on the edges or corners of LCD TVs.
Dirty Screen Effect
The Dirty Screen Effect is an effect caused by the backlight, local dimming or anti-reflective coating. The same color looks slightly different in different areas of the screen. This is particularly annoying when watching sports.
Judder is the term for single frames staying on the screen longer than other frames. This inconsistency is due to the input frequency mismatching the TV’s frequency. For example when displaying 24p content on a 60Hz TV the TV has to display every second frame 2 or 3 times (3:2 Pulldown) as 24 doesn’t fit evenly into 60.
Screen-Tearing is an image error that can occur in both videos and games. It occurs when the display and the graphics card are not sufficiently synchronized with each other and the refresh rate of the TV is not sufficient to display all frames transmitted by the graphics card. This may cause that both images are displayed fragmented on the screen. For example, the upper part of the picture does not match the lower part and the overall result may appear cut or “torn”.
As static frames are displayed too long on the screen, motion might appear not fluid. This is especially noticeable in long panning shots. To fight this a TV can use motion interpolation.
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