You’ve arrived home with your gorgeous new HDTV and you can’t wait to start enjoying the cinematic viewing experience of a movie theater right in your living room. You get everything hooked up and you fire up all the components, and … you have the feeling that something is missing. The images on the screen don’t have the pop, the pizzazz that you were expecting. Before you box it back up and drag it back to the store, spend a little time with the controls. You may find that you can adjust the image settings so that you get the quality you are looking to get. In this article, you’ll learn about the brightness and HDTV contrast controls, how to adjust them properly, and what to look for as you make the changes.
The Key to Quality: HDTV Contrast
One of the most commonly cited specification for HDTVs is the contrast ratio. This is intended to be a measure of the difference between black — the darkest color that the display can create — and white, which is the brightest color. Contrast ratio is most strongly influenced by the black level.
Now, it would be nice if you could use the specifications published by the manufacturers to predict whether or not a certain HDTV will have good contrast, but that’s not the case. The way that manufacturers measure contrast is good at producing impressively high numbers, but they don’t do much for predicting what you’ll see when you turn on the screen.
Why should you care about good contrast in an HDTV? First, good contrast generally means that you will see good blacks on the screen. A good black has that deep, rich, velvet look that gives an almost three-dimensional feel to the image, making it look so deep that you could dive right into it. With strong blacks, the colors on the screen will seem to pop without being garish or too strong. Conversely, a set with poor contrast will look flat and washed out, like an overexposed photograph.
In addition to good contrast, you want to get as bright an image as possible, as this will look best under normal room lighting conditions. So how can you get the most out of your new HDTV? (Note that the steps described here in this article will work with any television or computer monitor; it does not have to be a high definition set.) You could hire a professional display calibrator to come and adjust your screen for you, but that can be an expensive choice. If you follow the easy procedures described here, you should get very close to the optimal settings for your display.
Get the Black Level Right
The first step is to get the black level adjusted correctly. The easiest way to do this is to put a still image on the screen that is mostly black. Set the room lighting to the levels that you’ll normally use when viewing the television. Open the menu for screen setting adjustments, and choose the Brightness setting.
What you want to do is increase the Brightness level as much as you can without increasing the black level. Look closely at a black section of the screen, and watch as you adjust the Brightness. Raise it until you see the black area change from black to dark gray, then drop it back until it is black again and doesn’t change if you lower the Brightness further. That point where the black is one step below where it turns dark gray is the setting you want.
Here are three examples that simulate how a screen might look with the Brightness set too low, too high, or at the correct level. (Note that if your computer monitor is not adjusted correctly, you may not see all the differences between these simulated images.)
If the Brightness is too low, then the black areas will look good. Unfortunately, dark shades of gray also will turn to black, and you’ll lose detail in the shadows. It will also tend to make colors too strong, so that they look electric.
If the Brightness is set too high, then you’ll see good detail in the shadowy areas, but the black level will turn to dark gray. In addition, the colors will look washed out and faded.
When the Brightness is set correctly, the black areas will still have a rich, dark black color, but you’ll also be able to see all the detail in the shadow areas. Colors will have plenty of zip, but they won’t have the unnatural hues that you get when Brightness is too low.
Setting the Contrast Level
At this point, you have set the television to give you the best blacks and dark level detail that it can give. Now you need to do the same thing for the lightest shades. Choose a different still image for this step: one that has detail in large light areas. This time we’ll start with the simulated image for the correct setting.
Note that the white granite on the side of the monument in the picture has a texture to it.
With the Contrast set too high, the detail on the side of the monument disappears, as it gets washed out. At this setting, you can’t see all the details of the highlights in the image.
As you lower the Contrast setting, the detail on the side of the monument will reappear. As you decrease the Contrast level further, however, no more detail will show up. To reach the correct Contrast adjustment, you should increase the setting until the highlight details begin to disappear, and then bring it back down one step.
If you want to go the extra mile, go back and check the Brightness setting again to make sure that changing the HDTV Contrast setting didn’t change it. Go back and forth between the HDTV Contrast and Brightness settings until you’ve got them both set correctly.
Using this technique, and adjusting the HDTV Contrast settings, you’ll end up with the brightest picture that will show you as much of the detail as it can, in both the shadow and highlight portions of an image. And then you can sit back, knowing that you’ve got the display set to deliver its best performance.