Translated literally, this anglicism means “delay in the entry”. The input lag thus designates the time elapsed between the moment when the image is generated by the source (the video game console or the PC) and the moment when it appears on the TV screen. With the Steam video games, the options are multifold.
During a game phase, a large input lag value results in a time difference between the moment when the action actually takes place in the game (console time = T0) and its display on TV (time set by the TV to display this action = T0 + 75 ms, for example). This is particularly critical in games for which reflexes are the key to victory, typically fighting games and FPS, but also piloting games. A TV with a low input lag allows you to react almost instantly to the situation, while a TV with a large input lag penalizes the player who will necessarily react with a slight delay, often fatal.
- As an indication, on a game broadcast in 60 fps (or 60 frames or second), an image is displayed every 16.6 ms. A TV with an input lag value of 50 ms, therefore, generates a delay in the display of 3 images compared to the triggering of the game action.
- Most of us are unable to detect an offset of less than 50 ms, but a regular player will take care to choose a television set whose input lag is at least less than 40 ms. The most demanding players with very sharp reflexes will turn to models whose input lag is less than 25 ms.
With a display delay of only 21 ms, the Samsung UE55KS8000 is a very good choice for video games. Unfortunately, this data is the great absent from the technical sheets of the manufacturers of televisions which do not communicate absolutely on this point, contrary to the manufacturers of PC screens. To find the best televisions in this area, you have to look for the info. Gaming forums are generally a good source of information. Some specialized sites list and classify many televisions according to their input lag value. This is particularly the case for the HD TV test and Display Lag sites.
Note: the input lag is different from the response time which designates the time taken by the pixels of the screen to go from white to black and then return to white (also called reactivity). This response time depends on the fluidity of the video on the screen.
What is the input lag due to?
This delay is due to three main stages in the process of transmitting and displaying an image: the acquisition by the television of the image emitted by the source, the processing of the image by the video processor of the television and the actual posting process.
The acquisition of the image by the television depends on the type of connection with the source: on a digital television (OLED, LCD LED, Plasma) with a source connected in HDMI, the acquisition time is minimal since the transmission is done in digital from source to screen. The image transmitted by the console can immediately be used by the television.