How To: Calibrate Your HDTV

Back in the days when a decent TV cost $4,000, I never hesitated to recommend spending $300 or so on professional calibration.

But now you can get a pretty good set for less than $1,000. Far be it from me to tell you what your priorities should be, but to me, spending three bills to have a $900 TV calibrated seems as silly installing a $10,000 Viking range a 30,000 mobile home. Does this harsh nancial reality leave TV bargain hunters at the mercy of the factory calibration? Absolutely not — at least not those bargain hunters are willing to spend a few bucks on a calibration disc and a few minutes reading the rest of this article.

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Sure, there are times when you need to call in a pro: if your picture is a real mess, or if you’re a demanding videophile who insists that your set deliver the absolute best picture it possibly can. Most of today’s TVs, though, are fairly well calibrated at the factory, and most of us are content to have them running at, say, 95% of their capabilities. A few basic adjustments are usually all that’s needed to get your TV looking good. The only things you need to make those adjustments are a Blu-ray Disc with the right test patterns and a little bit of knowledge.

The steps we’ll outline here will work great on anything from a $200 19-inch LCD TV to a $20,000 three-chip DLP projector. The only difference with a projector is that you have to center, zoom, and focus the image before you begin calibration. One bit of advice before we get started: It’s a good idea to let any TV, be it a flat-panel or a projector, warm up by displaying images for a minimum of 30 minutes before you calibrate it. Now, let’s get on with the calibration.

Getting the Right Calibration Disc
Trying to improve your TV’s picture by simply messing around with the controls is like trying to do an appendectomy by simply messing around with a scalpel: You’re almost certain to do more harm than good. Fortunately, the tools you need to properly adjust your TV’s controls are simple: a Blu-ray Disc player and a setup disc. We’ll assume you already have the player, so let’s find you a disc. At press time, there were three commercially available Blu-ray TV setup discs: Digital Video Essentials: HD Basics, Spears & Munsil High-Definition Benchmark Blu-ray Edition, and Disney’s WOW: World of Wonder. Prices for these discs vary, but each sells for about $25-$30. Trust me: It’ll be the best $25-$30 you ever spent on your home theater.

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Of the three, WOW is, not surprisingly, the disc most intended for consumers; it’s packed with clear, useful tutorials and includes a helpful printed manual. Spears & Munsil has tutorials, but it’s aimed more at enthusiasts who already have some inkling of what they’re doing, and Digital Video Essentials seems targeted more at professional technicians. That’s not to say Spears & Munsil and WOW are watered-down Calibration for Dummies productions (notwithstanding the eminently skippable primers in WOW, which are punctuated by “wacky” comments from the formerly lovable Goofy). On the contrary, all three discs have enough test patterns for basic setup, and I find certain of the innovative test patterns on WOW and Spears & Munsil more useful than some of the more traditional patterns on DVE. Spears & Munsil is, in my opinion, the quickest and easiest to navigate, followed by DVE, with WOW running third.

What Digital Video Essentials has that the others don’t are the “window” test patterns needed to calibrate a TV’s grayscale — in other words, to adjust the TV so that it delivers consistent color reproduction from the darkest areas of the picture to the lightest. Most TVs and projectors now offer easily accessible controls for fine-tuning grayscale reproduction; they’re usually labeled Gain and Bias, and there’s usually one each for red, green, and blue. But to calibrate a TV’s grayscale, you need a colorimeter, an instrument that measures color temperature — the color of white, gray, and black in kelvins. While there are a few low-cost colorimeters out there, the really accurate ones used by pros (including the reviewers at Sound+Vision) cost several thousand dollars.

Step 1: Starting Out Right
Before you calibrate your TV’s controls, you need to adjust your room lighting to the way it usually looks when you watch TV. It’s worth noting that the dimmer the room lights are, the better the image you’ll typically get. You’ll enjoy a picture with punchier contrast and better shadow detail, and you won’t have to worry so much about glare on your flat-panel TV’s screen.

Now pick the best picture mode from which to begin your adjustments. With most TVs, the best mode for a typical light-controlled living room is labeled Movie, Cinema, or Theater — or THX, if your TV happens to be THX-certified. First select this mode, and then choose the color-temperature setting that’s labeled Warm, or Low, or 6,500. Whites may look a little reddish at first, but after only a few minutes, you should notice that the colors look more natural.

Just by taking the TV off its factory preset, you’re already getting a more accurate picture than probably 98% of all the TV viewers out there. But we can do even better than that.

Now you need to deactivate all the automatic picture functions on your TV or projector. Pretty much anything labeled Dynamic or Automatic needs to be off. That includes any auto color, flesh-tone correction, and dynamic contrast modes, and, on projectors, dynamic or automatic iris features. You can use these features later if you like, but for proper calibration they should be switched off. Next, if you have a flat-panel LCD TV with an adjustable backlight level or a projector with a lamp-brightness adjustment, you’ll probably want to turn these down some. How bright you want them will depend on your taste and the level of ambient light in your surroundings. Start with a backlight setting at its midway point, or a lamp setting of Low or Theater. If it turns out the picture isn’t bright enough, turn up the backlight or lamp setting and recalibrate.

Finally, if your TV offers a gamma adjustment, select the one that’s labeled 2.2 or Film. If the labels are simply an arbitrary number range, consult your TV manual to find out which setting is recommended for watching movies. If your manual offers no help, WOW includes a test pattern that lets you measure the gamma of your display so you can find the setting closest to 2.2. Or you can put on a movie with a high-contrast look such as The Dark Knight and pick the gamma setting that looks best to you.

To tweak contrast with WOW, you adjust that control until only the stars marked as visible can be seen (below).

Step 2: Brightness and Contrast
Brightness and contrast are by far the most important adjustments you’ll make on your TV. Set them wrong and the picture may look too washed out or too dark, with limited detail in the lightest or darkest parts of the picture. What’s more, the ambient light in your room will affect your perception of these settings — and it’s highly unlikely that the guys who designed the TV had just your room in mind when they picked the factory default picture settings.

It’s easier to understand how the brightness and contrast controls work if you know their technical names: black level and white level. Brightness, or black level, adjusts how dim or bright the darkest parts of the picture look. Contrast, or white level, adjusts how dim or bright the brightest parts of the picture look. The idea is that you want to make the picture as dark as possible in the dark parts and as bright as possible in the bright parts, but without losing any picture detail in the process.

PLUGE is used to adjust black level. You boost the brightness until all bars can be seen (above), then back it down (below).

Start with the brightness control, which you adjust using a PLUGE pattern. This displays vertical below- and above-black bars set against a black background. To set the brightness, turn it up so that you can see all the bars clearly, then turn it down just to the point where the darkest (below-black) bar is indistinguishable from the black background. In addition to PLUGE, WOW offers a basic pattern comprising a series of dark stars; you adjust the brightness so that the stars marked as Visible are visible and the other ones aren’t. Now set the contrast. While Digital Video Essentials doesn’t have a contrast-adjustment pattern per se, Spears & Munsil and WOW have unique patterns that let you set contrast easily. The process is similar to using a PLUGE pattern. There’s a series of white objects (vertical bars on Spears & Munsil, stars on WOW) at different levels of brightness. On Spears & Munsil, you adjust the contrast so that all of the white bars are visible except the brightest one on the far right. (Incidentally, this pattern also includes dark bars that you can use to set brightness, but I suggest you ignore them. In my experience, they result in black level that’s too high.) On WOW, as with the brightness adjustment, you adjust the contrast so that the stars marked as visible are visible, and the other stars aren’t.

To adjust contrast with the Digital Video Essentials disc, you can use the vertical gray step pattern (also available on Spears & Munsil). This pattern shows vertical bars at different levels of brightness, from the darkest black to the whitest white. Turn the contrast up so that you can’t distinguish the brightest white bar from the next-brightest white bar. Next, turn it down just to the point where the division between the bars in the pattern is readily visible. Brightness and contrast controls tend to interact, so it’s a good idea to go back to the PLUGE pattern, check the brightness again, and readjust if necessary.

With DVE’s vertical gray step pattern, you adjust contrast until divisions between all steps become clear (below).

Step 3: Color and Tint
On most of today’s TVs, the color and tint (or hue) controls need little or no adjustment. You have to at least check them, though. Again, it helps to understand the actual functions of the controls before you adjust them.

Color refers to color saturation, or the intensity of the color. If you turn the color control all the way down, the picture will be black and white (or close to it), while if you turn it all the way up, the picture will look cartoonish or irradiated. Tint/hue refers to color phase, which has the effect of shifting the picture toward a reddish or greenish/yellowish hue.

For color and tint, use a blue fllter and adjust the controls until both sections of the vertical bars look even (below).

To adjust color and tint, put up a color-bars test pattern, which consists of seven vertical colored bars atop much shorter bars of different colors. Now look at the bars through the blue filter provided with the disc. (Some TVs and projectors offer a blue-only mode that makes the filter unnecessary.) You want to adjust the color and tint controls so that all the lighter-shaded bars (bars 1, 3, 5, and 7 as you go across the screen) have the same intensity, and the same intensity as the smaller bars below them.

Set the TV’s color control first by adjusting it until bars 1 and 7 (the white and blue bars) have the same intensity as the shorter bars below them. Now you should adjust the tint control the same way, using bars 3 and 5 (cyan and magenta). (Some displays may lock out the tint control on certain inputs and in certain modes.) You may notice that the color and tint controls interact, in which case you’ll have to find the combination that gives you the best overall result.

Step 4: Sharpness
While it might seem that you want your TV’s picture to look as sharp as possible, turning up the sharpness control is like cranking up the treble control on a stereo: You may get more apparent detail, but the result will be unnatural.

To set sharpness, you adjust that control until halos surrounding the lines in a sharpness pattern disappear (below). To set sharpness, select the Sharpness pattern from Spears & Munsil or WOW, or the Overscan pattern from Digital Video Essentials. At the factory sharpness setting (usually 50%), you may see ringing, or white halos around the black horizontal and vertical lines in the picture. Turn the sharpness control all the way down to the minimum setting, and then bring it up until you just start to see the white halos around the lines in the onscreen test pattern. Now ease it down until the lines thicken and the halos just disappear.

Step 5: Tweaking It Up
As you watch with your calibrated TV, you may find that the settings don’t seem right for certain movies or TV shows. You may find that you need different settings for daytime and nighttime viewing. You may find that the image looks a little too dark or bright with certain sources. (For example, the image put out by my DTV tuner is about two clicks darker than the image from my Blu-ray player.) Fortunately, most TVs give you a few different User modes in which you can store custom picture settings to suit these different situations. Now that you know how the controls work and what the picture is supposed to look like, you have all the knowledge you need to deal with these issues — and to enjoy a fantastic-looking picture every time you turn on your TV.

How To: Calibrate Your HDTV | Sound and Vision Magazine.

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