by jakeludington.com
The wall of HDTV screens at the local electronics retailers calls out to me begging for my undivided attention in an unhealthy Poltergeist sort of way. On the retail sales floor all the pictures look super bright and it can be hard to distinguish which model offers the best grayscale shading and accurate color presentation without closer examination. As much as I prefer shopping online for everything, you don't really get a sense for which screen is best for your entertainment room without seeing it in person. Before you have the delivery guys drop a screen off on your doorstep, there's several key things you need to try before you buy.
Make Sure It's HDTV
Before you produce your plastic in the checkout line, make sure you know what you're buying. This seems like good advice for any purchase in the $1000+ price range, but few home electronics purchases are as confusing as HDTV. Many of the screens at the lower end of the price spectrum are actually Enhanced Definition TV screens, rather than being truly HD capable. EDTV is limited to 480p progressive-scan image quality, which looks better than standard definition and is the same resolution found in most DVD material available today. These screens can play HDTV signals from higher resolution sources like HDTV cable boxes or HDTV tuners by down-sampling the image from 720p or 1080i to 480p. HDTV-ready screens are exactly that, ready to receive an HDTV signal from an external source. These offerings rely on the cable box from your local provider or an external HDTV tuner to handle the signal processing before sending it to the screen and are capable of rendering HDTV resolutions. A true HDTV contains a built-in ATSC tuner/decoder capable of translating an HDTV signal at 720p or better resolution without requiring additional hardware. If you plan on getting all your HDTV content through a service provider, this may not be a major concern, but it's still something to consider in the purchase process.
Fullscreen Video on Your Widescreen
Most television broadcasts are meant to be shown in the standard fullscreen 4:3 aspect ratio of your old 27-inch television. Couple this with an archive of old fullscreen VHS and DVD movies and you may be watching a great deal of video that was never properly formatted for the current assortment of widescreen 16:9 aspect ratio HDTV screens. Consumer electronics manufacturers deal with this in different ways. My preferred method of viewing 4:3 video is in its original shape, which results in black bars appearing on either side of the image making use of approximately two-thirds of the widescreen viewing area. A second option is to stretch the 4:3 image to fit the full 16:9 screen. If stretching the picture to fill the entire screen is your preferred method of viewing, make sure the screen stretches both vertically and horizontally. Some budget HDTV screens only do a horizontal stretch, which results in picture distortion. The downside to stretching the picture is that you generally lose some portion of the top and bottom of the original image in the process of reducing distortion. If you want television broadcasts to fill the 16:9 screen, make sure the picture stretching feature does a stretch of both horizontal and vertical.
Standard Definition TV on a High Definition Screen
Unless your screen is dedicated to watching movies and the few shows broadcast in high 
definition, the majority of programming you watch will remain standard definition for the foreseeable future. To that end, an important factor in choosing an HD screen is how well it handles standard definition 480i video (digital cable signals are, in theory, progressive scan but translated to interlaced formats to accommodate the majority of televisions). HDTV generally reformats the content through a process known as upsampling or upconversion, which converts the interlaced content to 480p progressive scan, which is the same resolution found on DVD movies. A chip inside the television handles this conversion and some do it better than others. The most accurate upconversion processors are made by a company called Faroudja, which also packages its technology on boards from Genesis Microchip. Look for DCDi and TrueLife deinterlacing and image enhancement as part of a screen's feature set to make sure you are getting the best possible processing for standard definition video.
definition, the majority of programming you watch will remain standard definition for the foreseeable future. To that end, an important factor in choosing an HD screen is how well it handles standard definition 480i video (digital cable signals are, in theory, progressive scan but translated to interlaced formats to accommodate the majority of televisions). HDTV generally reformats the content through a process known as upsampling or upconversion, which converts the interlaced content to 480p progressive scan, which is the same resolution found on DVD movies. A chip inside the television handles this conversion and some do it better than others. The most accurate upconversion processors are made by a company called Faroudja, which also packages its technology on boards from Genesis Microchip. Look for DCDi and TrueLife deinterlacing and image enhancement as part of a screen's feature set to make sure you are getting the best possible processing for standard definition video.Truth in Picture Quality
There are two types of stores to shop at when choosing an HDTV. The boutique home theater companies with showrooms that attempt to emulate a true home theater, with the lights turned down and the screens calibrated for optimal viewing are one type of store. Wall of television retailers like Best Buy and Circuit City are the more common variety. While the boutique stores offer better informed personnel and an accurate representation of what you might experience at home, it's hard to ignore the discount pricing of the warehouse stores. To make sure you walk out of any retailer with the best possible screen for your budget, make a few adjustments to the demonstration models to get a real sense for what the screen is capable of.
Close inspection of the picture on any of the screens on the showroom floor of the big box retailers will likely reveal the contrast and sharpness skewed to either compensate for the harsh lighting of the sales floor or to try and beat out the screen next to it. For a real sense of what the screen actually looks like, you need to make some adjustments to bring the picture back to reality. If the remote for a screen you are interested isn't readily available for testing, have a salesperson track it down so you can tweak a few settings. First, move the contrast back to a level where everything on the screen blends more naturally. Adjust the sharpness to remove the ghosted edges from objects on the screen. Turn off any automatic picture correction features like skin-tone color correction and image noise reduction. Finally, change the color-temperature setting to 6500 K (for kelvins not kilobytes) to eliminate any bluish or redish tint that might make the onscreen picture look unnatural.
If the sales people question these adjustments, take your business elsewhere - this is the only way you can be certain the screen produces a good clear picture. In many cases, paying a few dollars more for the attention to detail provided by the boutique retailers may result in a purchase you remain happy with for the life of the screen.
A Touch of Grayscale
Black and white details make up the largest percentage of all color information in a television picture. The one area where most CRT screens still beat Plasma, DLP, and LCD is in the ability to recreate accurate black color on screen. Depending on color temperature settings of the screen, white may also get a bluish or reddish cast. It's possible to find great colors in all formats, but only through careful shopping.
As mentioned above, the NTSC declared 6500 K to be the official color temperature for United States TVs, which translates to the color temperature of the sun at high Noon on the first Wednesday in June in a small town outside Fargo, ND (or more accurately, the color temperature of sunlight when not obscured by things like proximity to the horizon, fog, smog and other light-altering airborne debris). If you don't set the color temperature of the screen as close as possible to the conditions used by the studio creating the movie or TV show you watch, your mileage may vary with how your screen recreates the image. Setting the temperature to the NTSC equivalent of normal also gives you a more accurate representation of how the screen you're testing handles shades of grey. The best test for checking out gray shading is to find your favorite movie with well-lit dark scenes, which sounds like an oxymoron, but there are dark scenes that are just plain dark and dark scenes that look superbly executed from a lighting perspective; Lord of the Rings has some good ones in all three movies.
Bringing it Home
Your final purchase decision ultimately will boil down to a compromise of screen size, available space in your entertainment room, what some might refer to as a spouse acceptance factor (as in, what will your husband or wife let you get away with) and most importantly - budget. By looking carefully at the little details before you buy, you'll come home with the best solution no matter how much of the family vacation fund you siphon off to feed your entertainment addiction.
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