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If you are a gamer, TVs are now also awful for playing games, due to the built in lag between the TV receiving a signal and displaying it. On a CRT it was insta
by mrcharles 15y ago
If you are a gamer, TVs are now also awful for playing games, due to the built in lag between the TV receiving a signal and displaying it. On a CRT it was instantaneous, as game console data streams were sent basically straight to the electron gun -- nowadays there's a massive amount of processing before the signal is on screen.
This manifests primarily in a feel of poor controls, or a game not doing what you tried to do.
Good HDTVs will give you 100ms of lag or so, bad ones can be in excess of 400ms. With most games nowadays running at 30fps, that's between 3 and 13 game frames of lag.
It's pretty absurd the difference this makes, and as a game developer I have to fight with it constantly and it is infuriating.
- sukuriant 15y agoI don't think I experience this problem. This may just be me, though; or, perhaps it's because everyone has these problems that we're on a level playing field. Also, I disable the vast majority of these post-processing features the TV provides. I'm a purist and a photographer by hobby and I can see all the 'fixing' that is done in in-TV post-processing, and it looks bad, less sharp, etc, to me. That may affect my experience... Or perhaps I just buy nice TV's (for the same reasons)
- mrcharles 15y agoDisabling those features generally helps but does not remove the lag. It is pretty difficult to see it in action, as it's more of a subconscious issue. A great litmus test is Assassin's Creed 2. I worked on that, and for all of development I had a CRT hooked to my dev kit. The game was always super responsive and I never missed a jump. And then, playing at home on my LCD TV... it was kind of insane the difference. It suddenly felt kind of mushy, and kind of like I was fighting the controls. The reality is that we as developers do as much as possible to hide it, but it's still there if you know what to look for.
- shasta 15y agoThe way you're describing the feeling puts it into the 10-40ms range. In the 100-400ms range you'd immediately and consciously wonder WTF was wrong with the game.
- mrcharles 15y agoYou'd think that, but you are wrong. Games like Uncharted have a built in 60ms of input lag due to multithreading of the game engine renderer, and that's before your TV, which I guarantee you, likely adds another 60 at least, unless you spent hours and hours researching and got the Uber Ultimate Gamer TV of the Month. In fact, Assassin's Creed 2 has 100ms of built in lag due to renderer multithreading. That means it takes a minimum of 100ms for the game engine to render the first frame of a reaction to your input press. It sounds crazy when it's all listed out, but I assure you it is not only real but something you deal with every time you play a game, even though you don't notice.
- InclinedPlane 15y agoMost hdtvs have a setting which will skip a lot of processing and reduce lag. Alternately, you can do research to find a tv without much lag.
- mrcharles 15y agoYour best bet if you are worried by lag is a PC monitor. But I don't think I've ever seen an HDTV that was verified to be below 60-100ms of image lag. Also, doing that research is nearly impossible and will in general result in a TV that's inferior for the majority of what you'd do with it.
- tseabrooks 15y agoI used to write SW for TVs... Any HDTV worth it's salt should have a "game mode" if it doesn't take it back and buy a nicer one.
- mrcharles 15y agoYeah but Game Mode still doesn't provide 0ms of image lag.
- Edootjuh 15y agoRight. Just the fact that it's digital means that it has to buffer at least a frame before it can be displayed.
- Retric 15y agoI don't think a monitor needs to buffer the full image before you display it just because it's analog data. It really just depends on how the internal bandwidth is setup on the tv vs how the data is sent to it. (AKA if each pixel is updated in order or if each line of TV is updated in parallel etc.) Worst case you might update the immage left to right but receive the signal top to bottom.
- tseabrooks 15y agoOf course not. Even the best lcd monitors are at 2ms lag. However, 'Game Mode' does provide a much better experience that even the most hardcore console gamer won't notice. A PC gamer might notice when approaching SC/SC2 APM. I think the takeaway should be that a TV with game mode will be great for console games and PC gamers should steer clear of TVs as monitors.
- mrcharles 15y agoThat's not the same lag. I'm not talking about the time it takes for the TV to completely change pixels -- that lag happens after the TV has decided to put the image on screen, and is largely not a big deal -- as long as the image has started changing, the player can understand the new scene. I'm talking about the time it takes for the TV to tell the pixels to change.
- brigade 15y agoAnother fun thing with processing that most people don't realize: almost all TVs will internally convert the input signal to YCbCr 4:2:2 for all this processing. Even though data is practically always transmitted as 4:4:4 over HDMI, and has to be converted back to RGB 4:4:4 to be displayed on the panel. So if you have red/blue text (or anything with red/blue detail) looking awful, like it was lower resolution than it is, you have the TV to thank for that. EDIT: to clarify, this doesn't apply if the text is a part of a movie (then you blame the codec for that, not the TV)
- jpdoctor 15y agoNone of the broadcasts are 4:4:4, nor are the DVDs. Hell, some of those HD broadcasts are 4:2:0 in order to reduce bandwidth.
- brigade 15y agoSome? Practically every encoded video intended for end-users is 4:2:0 (and certainly everything in HDTV, Blu-ray, and DVD.) I meant mainly for consoles, computers, and subtitles (though for subtitles it also depends on your DVD player) so I amended my post.
- jpdoctor 15y ago> and certainly everything in HDTV, Blu-ray, and DVD. The HD broadcasts are 4:2:2, more often than not. There are a few stations that have their video servers down at 4:2:0, but many of those are scheduled to upgrade over the next 2 years. Edit: The servers are 422, but the broadcasts are 420, as brigade points out. (The edit tag on my original comment has already expired. Grrr.)
- brigade 15y agoATSC only allows 4:2:0 in MPEG-2 (ATSC A/53 part 4 section 6.1.3) or H.264 high profile (which is restricted to 4:2:0). I'm admittedly not familiar with other countries, but I would be incredibly surprised if any of them allowed 4:2:2.
- kevinalexbrown 15y agoSo 100 ms is on about human eye-hand reaction time. Not that humans think in discrete chunks, but 100-400ms is like 1-4 extra responses, which makes game play quite different. Also, I know people will say "Game Mode!" but obviously, as a dev you can't just assume your end users will do that.
- Timothee 15y agoIs that what "game mode" is? I had always thought it was just changing the preset of brightness/contrast/etc. but is it also trying to reduce latency? (I'm not a gamer)
- endianswap 15y agoUsually it turns off all of the filters/post-processing steps and tries to mimick the response times of CRT displays more closely by sending the framebuffer to the screen as soon as possible. The works to varying degrees of success on a per-model basis. Just check out forums discussing which television to buy when you want to play music/rhythm games (like Guitar Hero) to read a lot more details about specific displays.
- speleding 15y agoGuitar hero, and most other rhythm games have a configuration option to put in a delay so that the game and sound match up with your screen again. For shooters that wouldn't help, of course, so there you need a fast screen.
- tseabrooks 15y agoI think the only people that tend to notice the difference between 100ms and 400ms are the more... ardent players... and those guys better damn well know what game mode is.
- tylerneylon 15y agoI disagree. 400ms is noticeable lag to anyone, still so against 100ms. Run this in bash, and imagine this lag in a game you're playing, as the time from when you hit a button on a controller to when you see the response on screen: $ sleep .1 $ sleep .4
- shasta 15y agoUh, four tenths of a second to change the camera angle would make every 3d game completely and totally unplayable. Even one tenth would have everyone up in arms about how terrible every game is. Maybe you meant 10 and 40ms.
- JoshTriplett 15y ago> Uh, four tenths of a second to change the camera angle would make every 3d game completely and totally unplayable. Even one tenth would have everyone up in arms about how terrible every game is. Maybe you meant 10 and 40ms. No, as disturbing as it sounds, real TVs really do have hundreds of milliseconds of lag. Games that care deeply about precision timing, notably rhythm games like Guitar Hero, actually have HDTV lag settings to change the offsets between audio, video, and input, so that you can actually strum based on what you see and hear and not miss every note.
- shasta 15y agoCitation? sites.google.com/site/hdtvlag/results shows some tests that show it's usually under 100ms for a wide range of TVs. That's bad but more believable. 400ms of latency is not believable. Such a TV would be unsuitable for real time games. Full stop.
- JoshTriplett 15y agoMost people don't buy HDTVs to play real-time games; they buy them to watch TV. As long as the TV delays the audio to match the video people won't notice when watching TV; DVRs commonly introduce similar amounts of lag. Looking at that site, they tested a relatively small number of TVs (only 14), and it sounds like they enabled "game mode" on any of the TVs that had it. I'll certainly acknowledge that 400ms represents the most extreme case, but 100-200ms or more happens pretty regularly, especially when not using "game mode" or equivalent.
- shasta 15y agoMost people don't play games, but I do. If even 200ms was common, it would be widely known among gamers that certain TVs are unsuitable for games. If you can't provide a citation, can you at least explain why you hold this belief? I'm obviously still incredulous.
- SilasX 15y agoThis is especially bad for rhythm games like DDR, where I learned about the problem the hard way. Even the "game" mode still introduces way too much lag. So I had to switch to the old CRT when playing my PS2 DDR games and thus had to keep it around.
- duskwuff 15y agoAnother form of awfulness I've often seen: Sixteen bazillion settings in the menus, and nothing in the manual to indicate what combination of settings will make the TV stop post-processing the image. One common offender is "Sharpness" settings. On many TVs, setting this to anything besides zero will make the TV apply a sharpening filter to the image, generating annoying halos around edges. Another common offender are "color" (especially "tone" and "contrast") settings. These were meaningful for CRT TVs, or when decoding broadcast video, but applying them to digital input is simply ridiculous -- especially when there's no obvious neutral setting.
- JoshTriplett 15y agoIt doesn't help that TVs frequently ship with all of those settings optimized for standing out in a showroom next to a dozen other TVs trying to do the same, rather than actually looking good in a living room.
- DenisM 15y agoThe best I found so far for modern TVs is the most expensive Samsung model, the xxx8000 series - only two frames of lag (30ms). Slightly less expensive xxx6400 has three frames, or a bit over 40 ms. This all measured in "Game mode". It's funny because a very old Westinghouse 37" LCD TV had between one and zero frames worth of lag. Also of note, the Onkio receiver I measured added two more frames of lag. So you should always play direct.
- Terretta 15y agoYes and yes, to both findings with both brands.