A television’s input lag is the amount of time that elapses between a picture being generated by a source and that image appearing onscreen. It’s only important for gamers, and even then, different gamers will have different sensitivity to lag. Over 50 ms is a detriment to competitive gamers, over 75 ms will bother regular gamers who are playing fast games, and over 100 ms will be noticeable by just about anyone. Over 125 ms makes it pretty much impossible to play fast-paced games.
Don't worry, most televisions can be adjusted so that they do not have high input lag. Try the following (which is how we set up the TVs in our tests):
Set the TV to Game or PC Mode
Disable all the television's settings
Additionally, you can try a lot of combinations of settings/modes/inputs.
To get the lowest input lag on Samsung TVs, you need to turn on Game mode. You can find it under System -> General. This usually drops the input lag by half.
Why is input lag important?
With fast-paced games like shooters and fighting games, quick reflexes are key. Lower input lag can mean the difference between a well-timed reaction that gains you the upper hand and a move that takes too long to register and ends up countered by the opponent before it can ever be performed. This lag doesn’t matter for watching movies, though, so unless you’re a gamer and are worried about PC peripheral lag, or Nintendo, Xbox One, or PS4 controller input lag (or other controllers too), you have nothing to worry about.
Why does the television take time to display a picture?
The total input lag time is the addition of three parts
There are three main functions that delay the television: acquiring the source image, processing the image, and displaying it.
Acquisition of the image
The source signal does not always come in a native format for the television. A digital television will have to convert the analog RGB component signal to digital. This conversion takes time. If you are seeing a lot of lag from an analog signal, try using a digital signal instead, because the television will need to do fewer operations to transform it. The closer you are to the television's native format, the less input lag you will have.
Once the image is in a format understandable by the video processor, it can change it. This includes:
Adding overlays (like menus)
Adjusting the colors and brightness
Interpolating the picture to match the television's refresh rate
Scaling it (720p -> 1080p)
The time this step takes is affected by the speed of the video processor and the amount of processing needed. Even if you cannot control the speed of the processor, you can control which operations it needs to do with the settings of the television. The more settings you enable, the more work the processor needs to achieve.
Some televisions have a dual core processor in them. This can help reducing the input lag if a lot of processing options are turned on.
Displaying the image
Once the television has processed the image, it is ready to be displayed on the screen. This is the step where the video processor sends the image to the screen. However, the screen cannot change its state instantly - the time will depend on the technology and components of the television. A plasma screen can change its picture faster than an LCD screen. You cannot control the time of that phase; it is fixed per television.
How is it measured?
An input lag of 40ms can be seen on the television.
Input lag is not an official television specification because it depends on two varying factors: the type of source and the settings of the television. The easiest way you can measure it is by connecting a computer to the TV and displaying the same timer on both screens. You can find such a timer here. Then, if you take a picture of both screens, the time difference will be your input lag. This is, however, an approximation, because your computer does not necessarily output both signals at the same time. For example, the setup to the right indicates an input lag of 40ms (1:06:260 – 1:06:220).
In our tests, we measure it using a dedicated device made just for this: the Leo Bodnar tool. This is a lot more accurate than the two screens method (except for with plasma TVs).
Television makers know that adding a lot of video processing increases input lag, which is why they usually include a gaming mode. Gaming mode will disable some of the television's most time-consuming processing. However, the gaming mode is not necessarily the setting that guarantees the lowest input lag of the television; you will sometimes need to play with the other settings to get the optimal input lag time.
I love Panasonic ST60. There's some many pros to this TV, but I read a lot of reviews that mention lag issues, and advice that said not to buy this TV if you are a gamer. Should I buy it, or what do you recommend? Max budget is ST60 range and I'm buying this TV to play PS4.
We tested 54.2ms on it, which is average. It is definitely playable. Most people cannot notice an input lag of under 75ms, so I wouldn't worry about it.
So all these TV's are horrible compared to 5ms tv/monitors I see all around the internet? Or is the 5ms a lie?
The 5 ms that you are referring to is not the input lag, it is the response time. They are unrelated. The input lag (15-50 ms range) is the time between the input and the display. The response time (4ms-12ms range) is the time a pixel takes to switch to another color (usually measured from gray to gray).
They do have input lag, but it is a lot less than today's televisions. They are analog televisions: the picture information is not a series of 1s and 0s, but is a continuous signal. They don't have a video processor at all; the only processing that they do are very basic, and analogic only. The signal can go straight from the input to the cathode tube without waiting to be digitized or processed. They are a lot quicker at displaying an image.
I just got a Sharp 70 inch LC-70TQ15U. Played it today and it didn't have game mode on and it felt sluggish. Wondering if you tested these, and if so, what they tested at. Also, would game mode improve the feel on this model?
Unfortunately, we did not test this TV, so we can't properly comment on its input lag. Game mode should reduce input lag, so try playing with that enabled and see if it improves.
Could you do a video with 2 TVs side by side? One with bad input lag and the other with excellent input lag, and then load up a first person shooter then just look from left to right and make the video slow motion? That would be very informative for people to really see what input lag can do in a video game that needs quick reflexes.
We could, but I don't think it would be very useful. The difference between a high input lag TV and a low one is about 30 ms, which also correspond to 1 frame of a 30fps game. Filming it in slow motion will just show one TV delayed by 1 frame, but it won't give you an idea of the feel. Instead, we've considered adding a tool to our website that adds a variable delay to a moving object, so you could experience it. The problem with this, though, is your computer screen also has an input lag, which would skew the demonstration.
I'm an arcade gamer and have a bunch of arcade systems at home that use VGA, so I'm looking at a VGA-to-HDMI converter. These converters have lag ratings; 43 ms, for example. Do these converters "replace" the lag in your tests, or is it "additional" lag? For example, if the TV is rated 30 ms and I use a converter rated at 43 ms, will the TOTAL lag be 73 ms?
It's additional lag, unfortunately, so both lag times would stack.
According to your Settings in the review for the LG EC9300, you ask us to change it to Game mode then copy your settings. Game mode doesn't have the same calibration settings as the Expert 1 picture mode you calibrated for. When you do calibrations for reviews, can you include the settings for Game mode and the usual Cinema/Expert/ISF modes as well? Also, can you provide the Game Mode calibration settings for the LG EC9300 if you have them available?
When we say to copy the settings, we just mean the ones that are available. We didn't express that as clearly as we would like, so we'll update the recommendation and try to be clearer on that point going forward.
And generally, apart from some of the settings being disabled, the settings within game mode aren't really different enough that it makes sense to give them their own section, so we likely won't be adding that. But thanks for the suggestion!
I have three questions. 1) Are you using the Leo Bodnar lag tester for your input lag tests? 2) Also, is it true that a plasma TV reports a higher input lag number because of its luminescence? 3) If so, should we expect a little better "feeling/experience" from a given plasma input lag number?
1) For 2014, yes, but for 2013 we used the two screens method. 2) Yes, it is true that the tool isn't accurate for plasma. The flickering of plasma TVs messes with the tool, because the tool is using a luminosity threshold to detect the lag, so it takes a little longer for the plasma to trigger it. 3) Indeed, maybe 10ms less.
I'm looking at a 55" TV for gaming. Low input lag is a focus for me. I also want to watch some movies and TV shows on it. Right now I'm looking at the LG LB6300, Sony W800B, and Samsung H6350. The Sony doesn't interest me, due to their mode that lowers motion blur. I don't want to have a dimmer TV with noticeable flicker. Which one do you feel would be best for gaming if you ignore Sony's Impulse mode? The other issue is that the LG 6300 is $899. I've also sometimes seen it at $799 on Amazon. The other two are around $1,100. Is it really worth the extra money for the Samsung or Sony? Right now the LG looks like the best choice. The only issue I see is the medium motion blur. I really appreciate your feedback, thanks!
Yes, the upgrade from the LG to Sony/Samsung is worth it. Far better contrast ratio and uniformity. If you don't plan on using Sony's Impulse mode, it is a tougher call compared to the Samsung H6350. Picture quality wise, they are very similar, so you won't be wrong either way. The difference in terms of input lag isn't very noticeable, so go for the Samsung H6350 (it has better extra features).
I have older Samsung TV's, 5-+ years old. Occasionally, while watching a DVD, I have this "what was that" moment. I'd characterize it as my screen seems to "freeze" for a fraction of a second, then continue on. Most of the time, my family never even notice it. I don't know if this is input lag, 3:2 pull, refresh rate, or what, but it bugs me a lot! I want to buy a new TV, that doesn't do this. Which spec do I watch for?
On your current TV, do you have Auto Motion plus enabled? That would explain why you're seeing the skipping, and disabling that feature would likely solve the problem.
If this is indeed the case, to avoid any of this kind of skipping in the future, just disable the motion interpolation feature on whichever TV you get.
Would you still get the 65 inch JS8500 over the 7100 even though I like gaming? Seems like I get more bang for buck with the 8500. Price difference is 1699 for the 65 inch 7100 vs 2000 for the 65 inch 8500.
Basically, you get more features with the JS8500 like its wider color gamut and HDR support but those won't benefit gaming. If it is what you do the most and don't care too much about the added features, save the money and get the JU7100. You won't miss much as far as picture quality and you will get an even better input lag.
Is there any chance you can test the input lag on the Samsung f8500 plasma with the HDMI input named Game (instead of PC) and the TV in game mode? I have this TV and with the HDMI input relabeled to PC, the picture quality suffers too much. I have heard that recently Samsung sent out a fix and the lowest input lag is with the HDMI named Game and Game Mode on.
Unfortunately, we do not have that TV with us anymore, so we cannot retest it.
It depends on your setup. If your computer has no problem rendering a game (it generates each frame in time for the monitor), there is no visual difference. In the case of the complete opposite, where it is just too slow, it won't help, because there will still be shutters. It is really just worth it in between those scenarios, where the computer is fast enough for most frames, but some frames lag behind.
So you are able to test Input Lag, which is great. I have read that there is no standard for testing response times in the gray-to-gray format, which many manufacturers are stating. Is there a way to test response times to standardize this figure? Also, will you be testing any OLED TVs (I know there aren't many), but just wondering. I am hoping this technology finally takes off and becomes mainstream, and would like to start seeing testing on these. Thanks.
We do an indirect test for response time through our motion blur test. Our testing rig tracks a moving image the same way an eye would, and records the visible blur that occurs while the object is in motion. The length of the trail is correlated with the TV's response time. You can see an explanation of our process here.
And yes, we do plan to test an OLED TV sometime this year.
I am looking for a TV to replace my CRT TV, both for retro gaming and competitive gaming. While I know any TV will have higher input lag than a CRT, but what would you recommend for a 32", 40", or 50" TV that will mostly be used for gaming? I haven't jumped onto a W800B just due to its ~$800 pricetag. Also, Component/Composite hookups aren't necessary, as I can use HDMI passthrough for that. Thanks!
The Vizio E-series is a great gaming TV, and costs much less than the W800B. It has low input lag and minimal motion blur, as well as good contrast. The upscaling isn't great, but you should still be able to play retro games comfortably. You can find the E-series at any of those sizes.
For input lag measurements for 4k TVs are you using an 4k signal? Would input lag be different using a 1080p signal? Thanks!
Unless specifically mentioned, it is via 1080p using our Leo Bodnar tool. On some TVs though, we tested it in 4k via a computer and using the less accurate 2 screens method, and the input lag was about 10ms higher.
Does an audio receiver impact the input lag time on a TV? Does it matter if it has up conversion vs. pass-through?
It could potentially affect the input lag (in both cases, upconversion or pass-through), but it depends on the receiver. The safest way is to plug the console directly to the TV, then send back the audio from the TV to the receiver (either via HDMI ARC or optical).
I'm not seeing any BenQ or ASUS monitor/TV products tested. Typically these "Gaming" monitors have super low input lag ratings, but I'm curious if they are actually as low as advertised? Any chance you could test a few of these? Specific models I would be interested in: BenQ XL2720Z and ASUS MX279H.
Unfortunately, we currently only test TVs, and don't have plans to expand to monitors for the time being.