| Video Noise November 2009
I Want to Make My Picture Better: Part One
 So you
have this HDTV and you’ve been watching it for a while, but you’re getting a
nagging feeling that the picture isn’t as good as it could be -- and you’re not
sure how to improve it. In fact, you’re not even sure you’d know if it was
better once you start messing with things. If that sounds familiar, this month’s and
next month’s columns will provide some guidance.
First, let’s define better. In my world, better
means more accurate. That is, the TV more accurately represents the movie or TV program as
it was originally captured. Video is very well defined in terms of quality. There are
standards for colors and shades of gray; shadow detail should be visible and not crushed
into black; highlights should be visible and not blown out or too dark; and color
shouldn’t be too intense, unless that’s how the movie was intended to look.
Every shade of gray should be as close as possible to the D65 point, which in the world of
xy color coordinates is x=.3127 and y=.328. You may have heard that 6500K is the ideal
color temperature, and it is. But color temperature doesn’t account for green. In
fact, you can achieve a color temperature of 6500K and still have way too much or too
little green. So instead of obsessing over color temperature, we should focus on the D65
point, which ensures that red, green, and blue are all in proportion, producing proper
shades of neutral gray and white. There are test patterns for measuring grayscale steps
and color, while other patterns help you adjust your controls by eye so you can improve
their accuracy without actual measurement.
To improve your picture, you have four options. You can:
- Adjust the user-menu controls by eye
- Adjust the user-menu controls with the assistance of a
test/setup disc in your Blu-ray or DVD player
- Purchase a colorimeter and software, and learn how to
calibrate your own TV
- Hire a professional calibrator
This month, we’ll cover the first two options.
Adjusting your menu controls without assistance
I’d like to offer guidance for adjusting your
controls, but it’s a real crap shoot when you have no reliable reference. All I can
suggest is that you disable all the controls in the user menu that have automatic
or dynamic in their name. Set the sharpness control to about half of the factory
default value. If the factory setting is 50, set it to 25. If the control is set to zero
and can be lowered to -30 and raised 30, you’ll never really know what the best
setting is without a test pattern. Ultimately, a test pattern is the only way to know
where it should be set. Sometimes zero is the right setting; other times it isn’t,
but only a test pattern will reveal the appropriate setting.
Any noise reduction or NR controls can almost always be set
to Low (or On if your only choices are On and Off). A few years ago these controls were so
severe that they often did more harm than good, but manufacturers have started providing
settings that can be used without harming good images. Noise-reduction settings typically
operate only on standard-definition programming, and conservative use of them in newer
video displays can actually be helpful. That said, setting them to Medium or High will
often impair quality. If you have a mode called Cinema, Movie, THX, Pure,
or Theater, select it. And if you have color-temperature settings like Warm,
Neutral, Standard, and Cool, the Warm setting will often be the most accurate. Be aware,
however, that if you’re used to the Cool setting, which makes the picture too blue,
the Warm setting might seem overly yellow for the first few days. Neutral may be the best
choice for a few HDTVs, but try Warm first. If it still seems too yellow after three days,
switch to Neutral.
Factory settings are almost always terrible for image
quality, and modes named Vivid or Dynamic are likely to be the worst
choices. Again, we’re assuming here that the highest-quality image is the most
accurate image. So if you’re watching football, the grass, uniforms, crowd, and sky
should look like what you’d see if you were at the game. But looking accurate
doesn’t always mean looking great. Take night games, for example. Some stadium lights
will make grass look blue -- even in person -- so adjusting the image to create a vivid
green will likely throw off the rest of the picture.
Adjusting your menu controls with a setup disc
 If you’re not very technical, the
Monster (yes, that Monster) HDTV Calibration Wizard setup disc (DVD
format) is probably your best choice. Everything it helps you with relies on simple photos
or simple moving images. You won’t learn much about your HDTV, but it will help you
adjust some controls much better than if you had no help.
If you want to learn more about your HDTV and how images
are made, as well as how controls will change the images, Digital Video Essentials: HD
Basics (Blu-ray) is by far the best disc out there. Shop around and you’ll find
it for as little as $16 from some reliable mail-order sources. As an example, the disc
will walk you through setting the brightness control, and if you ever need to recheck it,
you’ll be able to watch the tutorial again or go directly to a test pattern.
 If you already know the setup basics and you want a more technical disc, Spears
& Munsil’s High Definition Benchmark: Blu-ray Edition is about $25 at most
mail-order outlets. It doesn’t offer all the behind-the-scenes information and
explanations that you’ll find on the Digital Video Essentials disc, but if you
already understand the basics, the Spears & Munsil disc is the next level,
technically.
When you use one of these discs in a disc player, it’s
important not to have made any adjustments to the disc player that will alter the video.
The machine should simply send the disc’s data to the video display. This
doesn’t always happen, as some players have setup menu choices that can alter the
video in undesirable ways. For example, some Sony Blu-ray players let you choose between
Theater Room, Standard Room, or Bright Room. Among these, the only setting that won’t
change the video encoded on the disc is Standard Room, so you should never use the other
settings. If you own a disc player and you aren’t sure what some of the settings are,
or if they alter the video, you can search online owner forums for your particular machine
and hopefully learn from other owners what your settings will do and whether they’re
useful.
Next month we’ll take a look at your remaining options
for improving your picture.
. . . Doug Blackburn
db@hometheatersound.com |
