Because the Brightness and Contrast settings are so closely related, you may find in some cases that setting the proper White Level disturbs your setting of the Black Level (Brightness control). After setting the Contrast or Picture properly, go back and have another look at the PLUGE pattern and double-check the Black Level setting. If you’re very picky, or your TV lacks fine adjustments in the Brightness and Contrast controls, you may have to go back and forth a couple of times to be sure everything’s in order.
Sharpness is perhaps the most difficult element of TV calibration to explain, in part because it has more to do with how our eyes perceive an image than with anything that can be physically measured. For starters, it may help to understand what the Sharpness control can and cannot do. It cannot actually increase or decrease the physical resolution of your television: the resolution depends on the actual number of pixels available in the panel’s construction. What it can do, though, is make transitions between colors and shades appear sharper to the eye. You might initially think “the sharper the better,” and set the Sharpness to it’s maximum. The problem is, however, that as your TV increases the visible sharpness of an image, it also introduces unwanted artifacts that detract from accuracy, and even cause eyestrain during prolonged viewing.
The THX Optimizer does not include a Sharpness test pattern, but the DVE and AVIA discs include similar ones: a gray background featuring a black circle with lines radiating out towards the edges of the screen. This pattern is designed to give the sharpness of your TV an optimal test, but even without a test pattern you can see the effects of the Sharpness control: when the Sharpness setting exceeds the optimal level, you will see the artifacts of excessive sharpness around any edge between black and white, or between different colors on the screen. This usually appears as a either a dark “ghost” images of the edge, or a bright “halo” around objects in the picture. These artifacts, not present in the DVD signal, serve to highlight the edges and make appear more defined to the eye.
What you’re looking for as you adjust the Sharpness is to get the sharpest possible lines and text in the test pattern image, without the appearance of these false edges and the “halo” effect. Start by cranking up the Sharpness control until the halo artifacts are evident, then back down slowly to the point where they just disappear. At first glance, the picture may appear to the eye to be overly “soft,” or slightly blurry. But once your eyes get used to the Sharpness level, you’ll actually begin to see more detail, especially in moving images, because the edge effects won’t be distracting you from the intended image.
As with any setting, of course the final choice is up to you: some TVs, even good ones, have a naturally soft picture and you may find you actually like a little “extra” sharpening to get the most enjoyable effect. If nothing else, calibrating the Sharpness by this method will give a good baseline to start from.
COLOR SATURATION AND TINT
The Color adjustments are where having the proper calibration equipment can make all the difference in the world. Both the AVIA Guide to Home Theater and the Digital Video Essentials discs come packaged with blue, red, and green plastic films that accompany this part of the calibration. THX offers a set of blue filter glasses, which you can order through the THX website. The THX Optimizer combines Color and Tint on the same test, and the more sophisticated discs offer a couple of choices for color and tint tests.
Some of the language about Color adjustment, sometimes called Color Saturation, can be a bit hard to follow, but it all boils down to this: there is a level on your TV where the monitor is displaying precisely the color information sent to it by the DVD player, no more no less. That’s the level you’re looking for. Your TV probably comes out of the box set to artificially boost the color levels, which makes for a dramatic appearance on the sales floor, but ultimately is a distorted version of what the movie director intends you to see. Again, make doubly sure that your TV is in the most neutral color “mode” before undertaking this potion of the calibration: Vivid, Sports, or other modes are designed to artificially boost color saturation in different spectra, and may throw off your calibration considerably.
To set the Color or Saturation level, you’ll hold the blue-tinted filter in front of your eyes and adjust the Color control on your TV until the appropriate boxes match. Test patterns vary among calibration discs, so make sure you understand the directions for your particular system. Once you have the color saturation set to the most accurate level, you can move on to the Tint.