How to Adjust Your Picture Using Video Test Patterns

Why Adjust my TV?

Have you ever adjusted the picture controls on your TV? If you haven't, then you need to know that their current settings are most likely NOT intended for home use. In fact, most TVs are usually setup for viewing on a showroom floor when shoppers are looking for the brightest set that money can buy. Manufacturers have to assume that every TV leaving their factory has an equal chance of ending up on a sales floor. If the TVs were properly setup, they would look dull and muted compared to the inflated settings of other TVs. Advanced TV users know that showroom settings do not provide captivating images, with proper color and depth.

One big problem with TVs that are too bright is that they can be damaging to your eyes if viewed at night. If you often find it fatiguing to watch television at night or often get headaches when doing so, then your television is too bright. Proper calibration should reduce or eliminate these conditions. If you sit a good distance from a smaller display you may want to consider adding a backlight behind your TV. The human eye does not adjust for the brightness of the TV if majority of surrounding space is black. A backlight will help your eyes adjust properly.

About Adjustment

All color televisions provide the user with at least five basic adjustments. These adjustments are the keys to setting up your monitor to show you TV images the way they were intended to be seen. Many users try to adjust these settings by eye, which can be done with a relative degree of success. However, without a basic knowledge of what those controls really do to the picture, some often make the image worse than when they started. The challenge with proper TV adjustment is that without special patterns to put on the screen, its difficult to know if the controls are in the proper place.

Today, home users can adjust their TV sets with the aid of those special patterns, which are now available on DVD. You can get test patterns from a few different sources. Many commercial movies come with the THX optimizer in the special features section of the DVD. It's refreshing to see that studios are helping to provide tools to make the home viewers experience better. However, the THX optimizer does not include color filters, which are necessary to properly adjust color and tint. The two most popular complete kits for television adjustments are Avia and Video Essentials. Both are fantastic, however for home users Avia would probably be the better choice. It's easier to use, and it's black level patterns do not require your DVD to pass PLUGE signals (information below black), making it much more universal. Both kits include color filters. Since most home users use Avia, it's pattern names will be used in this article. Video Essentials has similar patterns to all of these. Any differences will be covered below.

Another way to calibrate your display is to hire an ISF technician do it for you. They have sophisticated equipment and access to additional adjustments within the TV's service menu. Their calibration will be more accurate than what you will be able to do yourself, however they usually charge around $400 to calibrate your display. You can get admirable results with the use of test patterns.

Getting Ready for Adjustment

Before you begin to make adjustments to your TV screen, allow the TV to play a TV program for at least 30 minutes prior to adjustment. Many TVs drift slightly as they approach their operating temperature.

Set the Lighting in Your Room

Set your lighting at a level that is common for your typical viewing. This will make a difference depending on the flexibility your TV allows. It's important that if you are adjusting for evening use, only adjust the TV with the lights off if that's where you normally have them.

• Some televisions allow only one universal setting for all inputs. If yours is one and you often view programs during the day and in the evening, you may want to turn up the lighting in the room for calibration. With only one setting for all inputs, some minor adjustment might be necessary during daytime use.

• Some TVs offer both a day and a night setting for individual or all inputs. If yours supports day and night for all of the TVs inputs, you'll want to configure it once during the day and again in the evening with your lighting set to where you would normally have it. If your TV supports separate settings for each input, you will only need to do it once, then copy the values over to the other inputs.

• Other televisions allow one individual setting per input. If this is the case, make your DVD input an evening setting then copy the values to all inputs. Adjust those settings for the sources that you would commonly watch during the daytime hours.

• Other TVs have different picture modes like sports, vivid, and standard. Adjust one of the modes for daytime use, and another for evening. Just remember which one is which.

The Controls

Once you have your lighting in the proper place and your adjustment options for your inputs down, you'll need to take a moment to familiarize yourself with your TV's video adjustment options.

In the menu for your TV, check out how many options it gives you for picture adjustment. You should see at least the following five settings:

• Contrast (picture)
• Brightness (black level)
• Sharpness (detail)
• Tint (hue)
• Color (saturation)

Your TV could have many more adjustment options. Standardize your image as much as possible before calibrating. Things like picture enhancers and black level expanders should be turned off. Some common ones are below:

• Color temperature (f. color) - turn this setting to warm or red.
• Black level expanders - disable
• Sharpness enhancers - disable
• Dynamic settings - turn to standard
• Edge enhancements (VSM) - disable
• Flesh Tone feature - disable

All manufacturers have their own names for common features. If you are unsure what it does, check your manual for a description.

Navigating the DVD

Once you have a handle on how to make adjustments, place the Avia DVD in your DVD player. Otherwise, at the main title menu choose "Advanced AVIA." Avia has an informative tutorial on how to use the basic patterns. If you choose to view it, do so now by selecting "basic video adjustments." If you would like to begin making adjustments without the tutorial, select "basic patterns." AVIA contains many different test patterns for video displays, the 5 most common patterns choices will appear on the display. For access to all of the video test patterns, select "video test patterns."

Calibrating Your Display

If your DVD player is connected to your display with a composite video cable (yellow RCA cable) or RF modulator, completely lower the color setting before you begin.

Needle Pulses and Steps

The needle pulses and steps pattern provides you with all of the necessary information needed to calibrate the contrast setting or white level on your TV set. The information you use on this screen will vary with the type of TV you own.

• Direct View & rear-projection TV's -- Lower the contrast setting to its minimum value. Keep an eye on the steps pattern, as well as the two black lines on the left and right sides of the lower half of the screen. Slowly increase contrast until the top step looks white, rather than a dull gray. Each step should be twice as bright as the step below it. If the black lines start bending outward as you increase contrast, you'll need to lower the setting to a level that makes them as straight as possible, even if you have to sacrifice some of the dynamic white. If, while raising the contrast the steps begin to bloom outward, immediately lower your contrast setting.

• Fixed-pixel displays -- Lower the contrast value to its minimum value. If you own a fixed pixel display such as an LCD or DLP TV, you'll need to keep an eye on the steps like above. However, you'll also need to watch the two moving bars in the white field at the bottom of the screen. You do not need to pay attention to the black lines. As you increase the contrast level, stop when the top step looks white, and when each step looks twice as bright as the one below it. If the moving bars in the white field disappear, lower contrast until they reappear.

Once this has been achieved, the contrast setting is complete. Move on to the next pattern.

Black Bars & Half-Gray The black bars and half gray pattern provides you all of the information necessary to calibrate your display's brightness setting. The adjustment is the same regardless of the TV you own. Increase brightness to its maximum value. You should see two bars moving back and forth in the left side of the screen.

Once you have identified the bars, decrease brightness to its minimum value. Increase brightness slowly, so that the left bar is nearly invisible and the right bar is visible on the black background. Once this is complete, your brightness control is properly set. You may want to go back to the Needle Pulses & Steps patter to verify your contrast setting because the contrast and brightness controls in your TV often interact.

If using a test pattern that involves the use of PLUGE signals, you'll need to verify that your DVD player can properly output these kinds of signals. If not, calibrating black level will be difficult. Look for the drop shadow behind the main object. Increase brightness from its minimum value until the drop shadow disappears. If done properly, the black level will be correct. For players that don't output PLUGE signals, you'll need to verify black level using the IRE steps at the top or bottom of the screen. On the PLUGE pattern with the THX optimizer, the seventh box should be your true black.

Sharpness

The sharpness control is very difficult to properly adjust on normal video material. The Sharpness pattern makes is a lot easier to set sharpness in the right place. The sharpness pattern has a lot different parts. At the top of the screen there is a frequency sweep. The bottom contains frequency patches, and the center has a large circle with some lines coming off of it. You will need to keep an eye on all parts of the screen when adjusting sharpness.

Increase sharpness to its maximum value. Examine the frequency sweep at the top of the screen. The right side of the sweep should be dramatically brighter than the rest of it, which would correspond to the patches below. If you examine the circle and lines in the center, you'll see that there is a false outline (like a white glow) surrounding these lines. Lower the sharpness setting until the frequency sweep is uniform in brightness all the way across, and the false outlines on in the center have disappeared. On some displays, the proper setting for sharpness is its lowest value.

Blue Bars

You will use the blue-bars setting to properly adjust the color and tint settings of the TV. Take out the two blue filters from the package and stack them together. When you look at the screen through them, you'll only be able to see the blue elements of the image.

The AVIA pattern contains four flashing squares, which makes it easier to know when color and tint are in the correct positions. Two squares are on the far left and right side of the screen, which are labeled saturation. The other two are in middle, which are labeled hue. To adjust, you'll need to alternately adjust the color and tint controls on your TV until the correct results are achieved.

When you have achieved the correct results, the blue bars should all have close to the same intensity of blue, and you should not be able to notice the squares flashing as much.

For other color patterns that do not use the flashing square, adjust color and tint until the blue bars have about the same intensity of blue.

Color Decoder Check

Many consumer displays do not have accurate color decoders, which often push one or more colors. If your decoder pushes blue or green, it is usually not objectionable. However, if your decoder pushes red, flesh tones will look over saturated and you will be unhappy with the picture. You can check your display for red push with the color decoder check pattern.

Look through the red color filter on the screen. The left column indicates the amount of red push. The block that has the same intensity of the background tells you the percentage push of that color. So, if the block that is labeled 20% is the correct intensity, then the TV pushes that color by 20%. If it is in the negatives, then the color decoder is underemphasizing that color.

The color decoder in most TVs is rarely adjustable. If red is being pushed by more than 10% you will need to lower overall color saturation until it is in the proper range. If your TV does have an adjustable color saturation, decrease red until the 0 block is the same intensity as the background. Any major adjustments of the color decoder may require you to readjust the color and tint settings using the blue bars pattern.

Finishing Up

Once all of these steps are complete, your television is properly adjusted. If you have gotten used to showroom settings, you'll immediately notice the image is darker and softer. Often, many want to reset the TV back to the way it was. Before you do, give yourself 2 weeks of viewing at the proper settings. You'll find that you see more detail and better colors. You'll also notice that nighttime viewing is significantly more comfortable than it used to be. Once you have adjusted to the new settings, you'll not want to return to the way it was.

http://www.techlore.com