Buyers Beware of New Unadjustable HDTVs
We’ve already warned you about Disposable HDTVs, sets you can’t get parts or repairs from the manufacturers. Next came “Unrepairble” TVs from Vizio and other set makers (here and here) that charge more for parts than buying the same TV as replacement, once the set goes beyond its one year factory warranty.
Now, a group of “No Name” HDTVs, primarily from China, are selling sets that lack a critical picture adjustment found in virtually every name brand television. It’s called the “Backlight” control. Buyers need to make sure the set they’re considering has this picture control. We explain why.
Original Picture Controls
In the days of bulky tube TVs (CRTs), the major picture adjustments were Contrast, Brightness, Color, Tint and Sharpness. Contrast is the white level. It determines how bright whites in the image are. Set it too low and the picture is flat and dull. Too high and the whites get blown out to the point where you can’t see the buttons on an announcers white shirt.
Brightness is the black level. Set it too low and all dark objects in the image disappear into black. Too high and the blacks become light gray and the picture is flat with no contrast.
Color controls color saturation. Tint allows flesh tones to look natural. Misadjusted faces will look either red or green. Sharpness is the last control. Too high and a glowing edge appears around objects on the screen. Too low and the image gets softer.
LCD and LED TVs have a “backlight” that creates the light you see. In the case of “normal” LCDS, this is a series of thin florescent tubes. With LED LCDs, it’s LEDs either on the edges of the screen, or arrayed on the back (facing you). The LCD screen itself, found inside all LCD and LED TVs, is like a color film slide. To view the image it needs to be illuminated by a light source behind the slide. That’s a bulb in the case of a slide projector, and the backlight in the case of LCD TVs.
Enter The Backlight Control
This is a control that was introduced a few years ago in virtually all major-brand LED and LCD TVs. It is as critical to a excellent image as the brightness and contrast controls. If the backlight is set too high, the dark areas in the image become washed out (see photo). Set too low, and the image is going to be too dark to view, even with the room lights turned off.
HD Guru researched a number of new “no name” brand TVs and found that several lack a backlight control. These are the price leader models found in holiday sale ads. They are names you’ve probably never heard of like Auria, Calypso, Skyworth and Spectre. Some, like Polaroid, were a once famous camera brand. The original Polaroid went bankrupt a number of years ago. A separate company bought the rights to the name and licenses it out. In this case to a Chinese maker of TVs. For more info on that, check out our Brand Names in Name Only article.
Adjusting The Backlight
Sets have adjustable backlights for several reasons. They will allow users to obtain the deepest blacks possible under your own particular ambient room light conditions. By leaving out the control the set maker simply has the bulbs cranked at their maximum level, making poor blacks and also wasting electricity. To properly adjust, you need to make sure the HDTV you are considering has this control and it needs to be adjusted it along with the brightness and contrast controls for the best looking image.
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