Posted on 10/19/2009 by Neversoft

Calibrating for Lag in GH5

Hey there. It seems some users are having trouble calibrating for lag with Guitar Hero 5, so here's a brief FAQ which should hopefully address your questions about setting it up, and about lag in general.

Q: What is lag?

A: "Lag" (or latency), is the time between the console sending an image or sound to the television and when it is output by the television. All televisions have a delay between when a signal is received by the TV, and when the image is displayed on the screen, some more than others. Earlier LCD and plasma television had lag which was much longer than on CRT televisions, and with the advent of music gaming around the same time flatscreens were becoming more popular, this was noticed more and more, since music games require precise timing.

The "Video Lag" and "Audio Lag" values in the calibration screen essentially tell the game "This is how long it takes between the game sending the video or audio signal, and when it is output by my television."

Imagine that you and a friend need to press two buttons at the same time on opposite ends of a football field. If your friend shouts to you at the moment he pushes his button, and you push your button when you hear him, you are going to be pushing your button after he pushes his, since it takes time for the sound of his shouting to reach you.

So, if you figure out how long it takes the sound to travel the length of the football field (a little over a quarter of a second, in case you’re wondering), and your friend shouts, then waits that amount of time before hitting his button, you will both press your buttons at the same time, assuming you have pretty good reflexes.

The time between his shouting and you hearing it is much like the lag experienced between the game console sending a signal to your TV, and when you actually see or hear it.

Q: Do I need to calibrate for lag?

A: If you are using a CRT television (i.e. not a flatscreen) you do not need to calibrate, unless something is seriously wrong with your TV. CRT's typically have a lag of less than 1ms. If you have an older LCD or plasma television, then you may need to calibrate for lag.

If you feel like you are hitting notes at the right time, but the game thinks you are hitting the notes late, you may need to set lag values, but you may also be just strumming late.

If you feel like you are hitting notes at the right time, but the game thinks you are hitting the notes early, then you are probably strumming early. This can become second nature if you're accustomed to playing on a laggy setup, and then calibrate it properly, since you may be used to strumming early to account for lag in the past.

If it is playable, but just seems a little off, try getting a friend to give a second opinion. Two people can play the same setup and have a different idea of whether it's calibrated properly or not. Reaction times, expectations of the song, and all sorts of stuff factor into one's perception of whether things are matching up exactly.

Q: How can I figure out how much lag to calibrate for?

A: One way is to look in your television's manual, or look up its product code online to find out the response time. Plugging in this value for both video and audio lag should work very well most of the time.

Or, if you know values from a previous Guitar Hero that give you a good result, those will be the same in Guitar Hero 5.

Q: I can't find out that info, how do I calibrate for lag?

A: Main Menu -> Options -> Calibrate Lag will get you into the calibration screen.

In Guitar Hero 5, we have changed the calibration to more accurately represent what one sees in the game. It does look different, which seems to be causing a little confusion. However, the actual calibration system under the hood is the same as always, so if you know what values worked for previous Guitar Hero games, manually adjust the values by selecting "Adjust Video Lag" and "Adjust Audio Lag" and you should be good.

If you don't know what values to use, pick the "Calibrate" selection, and follow these steps:

1. For the video calibration section, just strum the notes as they pass the strike line.
2. Once you're done with that, you should see a number next to Video Lag at the top.
3. For the next section, the notes will be hit automatically. Don't try to strum them. Instead, watch the notes as they explode and listen to the beep.
4. If they sound like they're happening at about the same time, go to the next step. Otherwise, strum up to increase delay of the audio until it matches up with the visual of the note hit flame.
5. Press Start to save the values of the calibration.
6. Select "Save and Exit" from the calibration menu.

The audio lag shouldn't be more than the video lag unless you have a strange setup such as using a CRT television and a fancy surround sound system that is running a bunch of effects on your audio. The audio lag should usually be between 0 and the amount of the video lag.

Q: What else can I do?

A: If your television has a "Game mode", this setting prioritizes reducing lag over the other processing the television does to the image, making it more responsive overall. Try this setting if your television has it available.

LCD and plasma televisions also have a "native resolution", which means that one pixel on your screen is used to display one pixel of the image. If you are displaying in anything but the native resolution, the television has to scale the image to fit into its screen. This scaling process takes time. Try and find out what the native resolution of your television is, and then use that setting on your console to reduce lag.

Q: Why don't you offer negative lag numbers?

A: Since the lag value is telling the game the time between when it sends the image and when the television displays the image, negative calibration values would mean that the TV displays the image before the console sends it. This would involve time travel, which is a feature we're looking into for Guitar Hero 47.

If you are consistently hitting notes before they get to the strike line because you see or hear the note early, you can simply increase the lag calibration for the other value. For example, if you're hearing the audio earlier than the video, increase the video lag number.

Q: I can't tell if 7ms or 8ms is the right amount, which one is it?

A: A millisecond (ms) is 1/1000th of a second. If you are actually able to distinguish between the two number on a game that runs at 60 frames a second, that's very impressive, but there's a good chance you might already have it set properly. The difference of a single millisecond is probably not going to make a huge difference to anyone who isn't a robot.

Most users will either not need calibration at all, or will need values between 10-40 ms.

Q: The video and audio go out of sync while I'm playing!

A: Well, that's not a question, but I'll try and help you out all the same. If this is happening all of a sudden, with a major shift between the audio and gameplay, it is not a problem with the calibration, but more likely that the audio and gameplay are getting out of sync entirely.

Try pausing and resuming the game so that the game can attempt to re-synchronize the audio streams to the gameplay.

Also check to see if your disc is damaged or scratched.

Finally, if the calibration seems to be moving around just slightly while you're playing, it may be that that's simply how the song flows naturally. Songs recorded with live instruments do not stay at a consistent tempo, since the original artists tend to speed up and slow down as they're playing. We've tempo-mapped all the songs to match this, which means that the speed of the songs really does change over time, both in the original song, and in gameplay.

I hope this answers some of your questions about lag and helps you to tune your game to work well for you.

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