HDTV Tech

It started out innocently enough, back in January 2000. ABC had concluded a season of Monday Night Football broadcasts in their 720p HDTV format and was putting the icing on the cake with an HD telecast of Super Bowl XXXIV from Atlanta, Georgia. Since I had watched a few of the MNF games in HD, I decided to set up a front projector and an HD monitor and invite some friends and neighbors over to give 'em a taste of sports in high definition. The game turned out to be a big hit. Over 30 folks attended and marveled at the widescreen images from my Sony VPL-VW10HT projector and Princeton AF3.0HD monitor. Never mind that I had to jury-rig an antenna on my rear deck and run coaxial cable into my basement to feed a single Panasonic set-top tuner, then use a video-distribution amplifier to run two component video feeds into my living room and my basement theater. Everyone was amazed at the picture quality and gorged themselves on a feast of wings, subs, pizza, chips, dip, and assorted desserts.

But manufacturers seldom offer much help in this, or even do their best to obfuscate. In their specs, descriptions, and promotional copy, one thing you won’t find clearly stated is what their products won’t do...

I have long been a complainer about motion blur with LCDs. It drives me crazy. I have gotten a lot of flack over the years for this, which I really couldn't care less about. (You don't see me making fun of your issues, do you?) I would just like to point this out: Why, if I weren't the only one who hated motion blur with LCDs, would nearly every LCD manufacturer come to market with 120-hertz LCD panels that claim to eliminate motion blur (a problem that they, surprisingly, haven't mentioned before)? Before I rub it in and say, "I told you so," let's look at what causes motion blur, why it may or may not be a big deal, and how a 120-Hz refresh rate can help solve the problem for LCDs.

Starting with the September issue (and now, online), we're adding a new measurement to our objective TV/projector tests. It's called "input lag" and while it's not as important as contrast ratio or color accuracy (which we already test for), it's an important metric for gamers, and anyone who notices issues with "lip sync."

So here's what it is, how we test for it, and what, if anything, you can do about it.