A co-worker with a fairly expensive home theater setup asked me over to his house the other day to troubleshoot an odd problem: He purchased Guitar Hero 2 for PS2, but couldn't hit anything properly. When I got there, I saw there was noticeable lag between the response of the controller and what we actually saw on screen. It was at least 2-3 frames, which is enough to really throw you off!

We traced the problem to his video processor (HDTV upscaler, deinterlacer, etc.) which he had recently added to his theater setup. By feeding the processor an interlaced signal, it was employing a deinterlacing strategy that needed 2 or 3 frames to work, and that meant 2-3 frames delay in the output. As you can imagine, this made playing games nearly impossible because the video lagged behind the actual game action.

Guitar Hero 2 contains a "lag offset" feature to try to deal with this, and it turns out that some people are using this to measure their home theater setups. We tried it, but all it did was reduce the error rate; you can't magically send your button presses forward in time to compensate for real lag.

The solution for him was to purchase the PS2 component cable, plug it directly into the TV (bypassing the video processor), and setting the PS2 output to 480p (progressive). But I wonder how many other people will spend thousands of dollars on home theater setups, only to run into the same problem and wonder what's going on...

Yet another reason why I won't buy an HD television (the main being the cost and that I could care less if it's better quality... my normal TV, and even my computer running a TV card, have high enough quality for me).

very nice article

Guess I got lucky; there's no noticable lag at all when upscaling on my HD set (I don't have a seperate processor, just using the built in upscaling/deinterlacing...). I have no problems playing Guitar Hero 1 & 2...I've heard of this issue but haven't seen it happen yet

edit
Oops, I guess I do have some lag; I just tried out Guitar Hero 2's callibration a bunch of times with results anywhere from 5ms to 70ms lag. Around 30-35ms was the most common result, so I'm guessing I actually have around 2 frames lag. Setting this hasn't helped my skill at the game at all though...

Was it an LCD TV or a plasma TV? I've heard that LCD TV's lag more than the plasmas. But I haven't confirmed if this is true or not.

It was actually one of the new Sony TVs, which use Sony's Silicon X-tal Reflective Display (SXRD) technology. It's essentially LCD on steroids. His TV itself has a response time of 2.5ms so the LCD technology itself doesn't produce lag (you may be thinking of "ghosting" or "blurring" which until 2006 was a problem with LCD monitors and TVs).

Maybe I was. I didn't know that newer LCD TVs had this feature. I have a plasma TV and my GameCube so far seems to work fine. But that doesn't mean that I will never experience a lag.

If your gamecube is connected directly to the TV, preferably with the hard-to-find component cable, then you most likely won't experience any lag at all.

Why?

Assuming it's a hi-def plasma tv then it will also have the same exact issue regardless if component/s-video/composite cables are used to connect directly to the tv. In any of those cases you're dealing with a 480i or 480p image that has to be upscaled to either 720p or 1080p; the tv will have built in circuitry to do this and depending on the quality may or may not have noticeable lag. Alternatively if an external video processor is used, then the tv doesn't need to upscale as it's now receiving an image in its native resolution, but you have to worry about whether or not the processor has any lag associated with it. In either case lag is a possibility depending on the equipment.

"Why?"

Because most typical deinterlacers in hidef TVs are substandard to reduce cost, and won't attempt such complicated 3-d filtering.

These external processors I wrote about are typically $1200-$1500 -- remember, that's something you buy in addition to the TV.

Personally, I think that proper calibration is more important than "image enhancement", but that's just me.

Ah ok, that makes sense


Yeah, I would tend to agree though I haven't seen many of these external processors in action to really compare the results. My tv offers two options for deinterlacing/scaling the image, and for movies/tv I find the basic option actually looks much better than the alleged fancier option.