Thursday, January 8, 2009

Fix that HDTV

Did you just get an HDTV for Christmas?  Or maybe you’ve had one for a while.  But in either case, I’m willing to bet you left most, if not all, of its picture adjustment controls are at their factory position.  (This information also applies to older standard definition televisions as well, though it isn’t as much of a problem on smaller sets.)

Most people (1) assume the factory knows what they are doing when they configure a television, or (2) they don’t know how to adjust their televisions for the best picture.  Well, guess what… nearly every manufacturer out there sets their televisions with some of the worst picture settings possible.  And the reason they do it is so that when you’re looking at them at the store, theirs looks “better” at first glance than the others.  Over the years the problem has gotten worse and worse, to the point now where the factory settings on some televisions makes them virtually unwatchable.

They also like to be able to advertise these fancy features that are intended to give you a better picture.  But what they aren’t going to tell you is that you’ll get a much more natural and pleasing picture by turning off all of the enhancement features that are available.  Every time you do anything to tweak the image, you are adding distortions and hiding the real picture.

How do we fix it?  Basically we need to adjust whatever settings we can to turn off all enhancements and processing on the image as much as we can. 

For example, the Sharpness control on every television I’ve ever seen is set WAY too high from the factory.  I know, you’re thinking, “but I like a sharp picture.”  Well, you’re getting more than you bargained for.  In order to add perceived sharpness to the picture, they have to also increase the visibility of noise in the picture (which then obscures real picture information).  If your picture ever looks really blocky or has any trace of highlights around objects, chances are it’s your sharpness control adding those artifacts.  They aren’t there in the original picture.  The solution?  Turn the sharpness control OFF, or all the way down, on most televisions.  Most televisions should have the setting turned completely off; only if you own a really high end set do the manufacturers allow any leeway.  If you are used to watching your TV with the sharpness turned too high, the picture might seem too soft at first, but after a while you’ll start to see detail that was being hidden by the noise your TV was adding previously.  And the picture will be much easier on your eyes to watch.

Here’s an example.  The following images are shown with the sharpness control turned off, at 50%, and at 100%.  Notice the clean edges on the one at left?  The other two add highlights (halos) around the edges of the text to make them appear more sharp, which in turn exaggerates the blockiness of the letters.  They’re destroying the original picture with the Sharpness control turned on.  (Image Source)

All other enhancement features should probably be turned off too.  The “noise reduction” and “edge enhancement” features on many TVs are turned on by default from the factory, but they remove real picture information and then add false data to compensate.  Turn off anything else that has “enhance” or “correct” in its name.

Any “dynamic picture” controls that you might have are probably bad, too.  With this feature turned on you’re basically telling your TV that you think it knows what is best with regard to how bright or dark the picture is; it is dynamically adjusting the brightness of your picture.  But there is no way the television can know how bright the picture is really supposed to be.  And besides, that movie you’re watching has already been setup with the correct levels of brightness.  Your TV doesn’t need to try to change it.

Most TVs also have their Color setting set too high too.  The proper setting is usually somewhere right in the middle of the available range, or slightly to the left of it.  If your reds or yellows seem outlandish, your Color control is too high.

If you have a Color Temperature control on your television, set it to Neutral, or your TV is intentionally shifting all colors toward orange or blue.  And if you remember from my photography class, orange and blue are opposites, and cancel each other out.  So if your TV is shifting the color toward orange (one of the Warm settings), anything that is supposed to be blue actually shows up more like a gray.  And vice versa.

Next, turn down your Brightness.  The television system was designed to carry picture information that is darker than its real black setting.  Many people turn up their Brightness control so they can see every little bit of detail in every shadow.  Wrong.  There are parts of the picture that are supposed to be invisible.  And if “black” on your TV looks even the least bit gray, turn down your Brightness control!

One setting that most manufacturers are generally getting right is the Picture or Contrast control, if you have an LCD or Plasma.  It should be somewhere around 95% of the maximum available setting on newer flat panel displays.  CRT (the old tubes) televisions, on the other hand, should have their contrast set right in the middle, or you risk burning out the TV too quickly, seeing gray objects displayed at white (with anything brighter losing all detail whatsoever) and are certainly seeing the size of your picture change when it goes from bright to dark.   The general rule for all televisions is, turn it up to the point where white looks white, but still retains fine detail.

And one last thing, it actually isn’t good for your eyes to watch television in a fully darkened room.  It is best to have at least a little light coming from around the television.  The professionals recommend a light at least 10% as bright as your television coming from behind the set (ambient light in a normally lit room qualifies) to avoid eye strain.

If you happen to have one of the DVDs out there that have the THX Optimizer (as several Disney films have had in the past), go through the instructions found on the disc.  While not perfect, it will go a long way toward getting you the best picture your television is capable of delivering.

Happy tweaking!

P.S. Some televisions use different settings for different inputs.  So once you finish setting your TV up for the best picture from DVD, you might need to do it all over again for your satellite or cable box, game console, or even over-the-air broadcasts.

1 comment:

Boy Mom said...

Hey Dr. HDTV,

Do you make house calls? We pay in cookies the flour and sugar kind not the technology kind ;)

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