As most home-theater enthusiasts know, THX has a long history of certifying audio products to conform to certain standards of performance in order to reliably replicate the content producers' intended experience at home. This was a natural outgrowth of the company's original mandate to do the same thing for mixing stages and commercial cinemas.

Recently, THX announced it would extend that process to video products, including flat-panel TVs. The first two such TV lines—LG's 50- and 60-inch PG60 and Panasonic's 50- and 58-inch PZ800 plasmas—were introduced at about the same time, and I've been eagerly waiting to see just what THX certification really means in terms of video performance. First up is the LG 50PG60, a 50-inch 1080p plasma TV that lists for $2700.

Features
The 50PG60's most prominent feature is THX certification. According to THX, its certification program has two primary goals—to drive quality in manufacturing and help simplify the consumer's buying decision by implementing a single testing methodology and specification.

Testing is divided into two categories—device performance, which includes things like contrast, grayscale, and color gamut, and video processing such as scaling, deinterlacing, and noise reduction. In addition, a certified TV must have a "THX mode," in which all parameters are preset to produce an image that conforms to the standards established for HDTVs. The 50PG60 offers such a mode, which locks out all picture controls except aspect ratio.

In addition to a THX preset mode, the 50PG60 offers extensive calibration controls that are much the same as in LG's 47LG60 LCD TV. For your convenience, I'll reiterate my discussion of this here, noting any differences along the way.

Like the LG60 LCDs, the PG60 plasmas offer a 10-point grayscale-calibration system. Most TVs offer a 2-point system, which lets a trained technician calibrate the low and high ends of the brightness range. But this is often insufficient to completely dial in the grayscale, which can easily deviate from the standard at brightness levels other than the two that were calibrated.

With a 10-point system, a technician can calibrate 10 different brightness levels independently. This takes longer than a 2-point system, but the end result is a nearly perfect grayscale (see Measurements). Interestingly, the PG60 offers both types of calibration systems. As always, don't attempt to calibrate this or any TV without the requisite skill and equipment—it's a job best left to professionals.

Another important feature is a color-management system (CMS), which lets a trained tech adjust the primary and secondary colors to more closely match where they are supposed to be. The tint and saturation of each color can be altered, but there is no intensity control for each color as there should be.

Many upscale TVs, including the PG60, offer ISF (Imaging Science Foundation) Day and Night modes. These allow a tech to lock in the calibration settings for different viewing conditions—one for daytime with ambient light and one for nighttime with no room light—so that they can't be inadvertently messed up. In fact, the THX mode can be calibrated in the service menu and saved as one of the ISF modes to prevent any tampering.

A side-mounted USB port lets you attach a storage device and display digital photos and play music files. Sharing photos in this way is a great feature, and you can play music stored on the same device to accompany a slideshow, but why you'd otherwise want to listen to music on any TV's sound system is beyond me.

The HDMI inputs are version 1.3, which means the TV can support Deep Color (higher bit depth for smoother gradations) and CEC (Consumer Electronics Control), which LG calls SimpLink. Interestingly, the product literature does not specify support for xvYCC, the expanded color gamut allowed by HDMI 1.3. Not that I'm complaining—no commercial content is produced using Deep Color or xvYCC, and I don't expect that to change any time soon, so these features are essentially useless.