Newcomers to Sound & Vision's HDTV test reports are likely to come across some tech talk that might seem confusing or arcane at first. The truth is, video technology has become much more complex since TV started to go digital and high-def nearly a decade ago, and a side effect of all that increased picture resolution and clarity has been mounds of strange new jargon. But jargon aside, many of the practices we use to test high-def sets actually go back to TV's pre-digital days. To put these practices into context, and to better relate them to the descriptive terms commonly found in S&V's HDTV test reports, we're going to dissect a typical review. (Pardon me for a second while I pull on rubber gloves and find a scalpel.) Once we're done, you'll know your Grayscale from your Overscan.

THE INTRODUCTION
The first section of a TV test report is dedicated to giving an overview of the product. It also describes notable characteristics — for example, the first 1080p-resolution plasma TV to break the $5,000 price threshold — and the set's overall position in both the market and the manufacturer's product line. From there we move on to features that distinguish the set or make it distinctive in its category. Looks also matter when it comes to an HDTV — remember, this is something you might be living with for the next 10 to 20 years — so we make a serious effort to describe its appearance and call out details that might not come across in the glossy photo that accompanies the review.

For new TVs, connectivity is extremely important: You need to know whether a particular set has the right type and number of inputs to accommodate the gear in your A/V system. We call out important jacks relevant to high-definition hookups, as well as mention any out-of-the-ordinary ones. A comprehensive list of inputs can also be found on the second page of the review in "Key Features" — a box giving exactly that, including screen resolution, the set's dimensions and weight, and the manufacturer's Web site and phone number. Back on the first page, a box called "The Short Form" provides a Snapshot evaluation of the product along with price information and helpful Plus and Minus bullet points.

The last thing that gets a look in the introduction is the TV's remote control, a photo of which can be found on the second page of the review. The key thing we're looking for here is ease of use in the dim-light environments that work best for watching movies. Some other points on our checklist: Does it have a backlit keypad? Are the buttons cleanly arranged and easy to locate? And with some new HDTVs sporting upwards of 10 video-input jacks, how simple is it to switch sources via the remote's keypad? (A set of Direct Input buttons gets a gold star.) Last but not least, we check out the Aspect Ratio (also known as Display, Picture Size, or Picture Shape) options for various signal formats.

SETUP
The next section, Setup, is where we cover the nuts and bolts of getting the TV to look its best. This often starts with a discussion of appropriate seating distance for the set's screen size and resolution, as well as any screen-glare issues — a factor with some plasma and rear-projection models — that might affect placement. But the primary focus of this section is an overview of video adjustments that the set supplies for tweaking pictures.

Most TVs provide a number of picture presets to automatically change the brightness, contrast, color balance, and, in some cases, sharpness of images. They also have presets that alter the picture's color for a cool (blue) balance or a warm (red) one. To show pictures with accurate color, TVs need to display images across the entire Grayscale — the range of gray steps between black and white — at a color temperature of 6,500 kelvins (K), which is a unit of measurement based on a theoretical "black body" heated to a specific temperature. This 6,500-K specification, roughly equivalent to the look of sunlight on a clear summer day, applies equally to both regular analog and high-definition digital TV.

Few TVs can hit the 6,500-K spec using out-of-the-box adjustments, but our Setup section identifies which combination of presets can bring you close to getting an accurate range of grayscale steps. We also indicate how flexible the set is in saving any custom picture adjustments you make and whether or not these can be stored independently for each video input. TVs from different makers often come with their own unique set of advanced picture adjustments. We call out the ones that are useful for getting good image quality, and we also indicate if any service-menu adjustments — a set of tweaks that aren't normally accessible to users but can be made by a certified technician — were required to get the TV up to snuff for the Performance section of our evaluation.

PERFORMANCE
Many criteria go into making a subjective evaluation of a TV's performance, but the Big Four are Color Balance, Detail, Black Depth/Contrast, and Shadow Detail. These characteristics are measured during the objective part of our evaluation, and the measurements ultimately go far toward shaping our subjective impressions.

Comments on Color Balance deal with the TV's ability to display a natural-looking range of colors. In particular, we look closely at skin-tone rendition and color saturation, or the richness of a specific hue, such as red or green, relative to other colors. Discussion of Detail covers the set's ability to display the full resolution contained in both standard- and high-def program formats, as well as how sharp those programs look when routed through the set's various video inputs. Black Depth and Contrast observations describe how dark the deepest shadows on the TV's screen appear, as well as how punchy and bright the highlights in pictures come across. Both characteristics can vary widely depending on the overall brightness level of programs, so we evaluate their consistency with a range of material. Lastly, comments on Shadow Detail focus on the TV's ability to show a range of dark gray steps in shadowy parts of pictures — particularly in dark scenes, which pose the biggest challenge to TVs.

Moving beyond the Big Four in the Performance section, we come to some more nitpicky points that also require scrutiny. Discussion of Uniformity describes the TV's ability to display pictures with even brightness levels at all points on the screen, as well as the screen's relative freedom from unnatural-looking color tints. Both issues are ones we've encountered mainly with LCD and LCoS models, though they're hardly exclusive to those technologies. Comments on Motion Rendition usually involve Video Processing — the set's performance when scaling both lower-rez material such as DVDs as well as 1080i (interlaced) high-def programs to the screen's native progressive pixel display. There's plenty that can go wrong during this process, often resulting in a softening of the picture or the introduction of jagged-looking artifacts on edge transitions. The final observations in the Performance section usually involve the set's noise-reduction processing — how effective it was in retaining detail when clearing up grainy-looking images.

BOTTOM LINE
By the time you get to the Bottom Line — after you've pored over the minutiae in the Test Bench box (detailed next) — you can look forward to reading a summary of both the good and the not-so-good points of the TV's features and performance. This is also where we pass judgment on how the set racks up value-wise against its immediate competition. You'll probably want to know if the TV gets an S&V recommendation. If that subject isn't addressed in the Bottom Line, a Certified and Recommended stamp on the first page of the review will clearly indicate an emphatic thumbs-up.

TEST BENCH
Our Test Bench box on the second page of the review contains a condensed version of the full lab report, which can be found in the Equipment section of our Web site. The provided chart is used mainly to illustrate the set's level of deviation from the 6,500-K standard — something known as Grayscale Tracking — both before and after any special adjustments performed during the evaluation. Of course, we'll also make a point of letting you know here how the set's post-adjustment tracking numbers measure up to those of an average TV of its type.

Other lab tests summarized in the "Test Bench" include Color Point Accuracy, Color Decoder Error, Overscan, Resolution, Uniformity, and Video Processing.

Color Point Accuracy indicates the TV's level of adherence to the SMPTE (Society for Motion Picture and Television Engineers) specification for high-definition red, green, and blue. Though it's not uncommon for a set to show some oversaturation on one or more of its color points, the closer it adheres to the spec, the better. Meanwhile, tests for Color Decoder Error show the TV's ability to accurately translate encoded color information from standard- and high-def sources (each format gets handled differently) for display on the set's screen. A 5% positive or negative red or green shift falls in the average range here, while numbers greater than that could indicate potentially image-degrading effects. Along with grayscale tracking, which is normally easy for a certified technician to adjust using specialized test equipment, both color-point accuracy and color-decoder error can potentially be improved by professional calibration.

Overscan is the amount of picture area that's cut off at the edges of a given set's screen. A minimal level of overscan (around 3T to 4% is the average) is actually a good thing when you're watching cable or broadcast TV programs, which often have unsightly synchronization data embedded at the extreme top and bottom of the image. For DVDs and high-def disc formats, however, a higher-than-average overscan level will lop off the edges of widescreen pictures — a source of profound irritation to movie buffs. Our Test Bench box lists overscan percentages for both the set's HDMI and component-video inputs, and we also indicate if any special modes are available to eliminate overscan completely.

Resolution measurements give a good indication of just how much detail a given set is capable of with high-def programs. We describe whether the TV was able to deliver the whole enchilada, as well as how its picture resolution fared with different inputs and signal formats, such as 1080i and 720p high-def. Finally, space permitting, we wrap up the Test Bench with more in-depth comments on Uniformity and Video Processing.

Well, there it is, laid out on the table for your inspection: Sound & Vision's procedure for HDTV test reports. And now that you know us a little better, we hope you'll find these reviews easier to read through and understand. Whether you're an old-timer or a newbie preparing for a dive into the intimidating process of shopping for a first HDTV, more knowledge equals more power when it comes to the increasingly complex world of digital television.

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