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How to optimize basic picture settings on a new TV
Start by examining the room where the display will be
located.
Having bright ambient light in the room will lead to
far different settings of the basic user controls than a light controlled environment.
That is why many manufacturers have Day/Night modes
or otherwise named settings that you can set up and then select when appropriate.
Next, ask yourself whether the display will be used
for critical film viewing or casual sitcom watching.
If you are a film buff that wants to become immersed
in the movie, the room should be darkened and the light from the display should not be so bright as to cause eyestrain. A
small low intensity backlight may be helpful as well.
On the other hand, if the TV is in the living room and
there are multiple distractions, settings of even the basic controls are not as important.
So, for serious viewing
The two most important things to get as correct as your
display can produce are the Black and White levels.
Black level controls (brightness) proper setting.
Use a pluge pattern from any Test disk or sub program from a DVD.
A Pluge pattern is one that generally has two bars against a black (absence of light) background. If you see the "below black"
bars your displays black level is set too high. The below black rectangle or left hand bar should reach the absence of light
and match the background first. If you were to continue to decrease the control to a point where the right hand bar or above
black rectangle disappears, you have gone too far and must increase the control until the above black bar/rectangle appears
while keeping the below black from showing up. One click will make the difference when you are close to correct.
White level controls (picture, contrast) proper
setting.
Crt based displays have an easy to recognize effect called Blooming. The peak white level should be set to below the point
where distortion of the picture occurs. Look at the top white box of a pluge pattern. Set the white control to a point where
the box seems to grow in size. Reduce the W/L control until the box attains the same size as the boxes below it. Find the
point where the box is as bright as it can be made, but does not grow (bloom) to any degree. You will now have to recheck
the black levels as the Black and White controls interact to a certain degree.
Black and White level for light engines and plasmas .
The black levels of these displays are getting better with every new
iteration. The use of Iris Control, which subjects the overall light emission in the same way a camera reduces light to the
film, is a potential step in the right direction. You still need to use the pluge pattern and to set the blacker than black
area to the same level as the background. The background itself will be brighter than that of a CRT, but the same use of the
user controls are necessary.
The white levels are a different matter. Light engines do not Bloom
so it is not as easy to see when the display is overdriven. A better test pattern with these displays is to use a 256-step
pattern showing the brightest 32 steps. Setting the white level control to a point where there is definition between the brightest
points with the brightest being white is correct. If you notice that several of the brightest boxes appear to be the same,
reduce the W/L control until you can see that only the brightest box is pure white. The smallest amount of difference between
the top two boxes is correct. If you do not have access to a test pattern with this level of accuracy, use at least a ten-step
grayscale pattern. It is critical to get this right with digital displays.
Again, though not to the same degree as CRT’s, there will be some interaction between black and white level controls,
so when done with one, check and recheck until a balance is attained.
Sharpness or Edge Enhancement controls.
Sharpness is probably the most misunderstood of user controls. Increasing
the "sharpness" actually causes the display to remove content that should be displayed. It does this by covering up the edges
or outlines of objects with white or black lines. It is best seen with this test pattern.
When you see fringing or shadows along the edges of the horizontal
and vertical lines, reduce the EE controls until the fringing in minimized or removed completely. While the perception that
the image is "softened", in actuality, you are now seeing the content as intended. Your eyes will adjust to this easily when
watching a good film from a HD or DVD source. When watching Standard Definition TV, using any controls available to help the
image may be necessary, as that image was never meant to be seen on a display larger than 19 inches measured diagonally.
Color and Tint Controls.
Last to do, and frankly the least controllable with user settings,
are your saturation and hue (color and tint) parameters. They will also interact so be ready to do some back and forth between
them.
With the use of user controls without the aid of measuring equipment,
you will need a Blue Bars SMPTE pattern and a blue gel filter. Set the color control to the point where the left hand gray
(top) over blue (bottom) is the same level as the right hand blue (top) over white (bottom). When complete and matched as
evenly as possible set the tint control to balance the cyan (top) over magenta (bottom) 3rd bar from left with
the opposite 5th bar. Again, the controls will interact on every type of display to a degree, so check you progress
often.
Now you have the color controls looking great on the test patterns,
but when you look at a sample scene from any source, your people have the look of being severely sunburned! The controls required
to alleviate this are not generally available in the user control area so you will have to compromise fully saturated color
scenes by reducing the color control (not tint) until proper skin tones are achieved. Hopefully, you may only have to reduce
the color control a few clicks.
If you notice that very dark areas in dark scenes have a hue that should be black or very dark
gray, you may be able to control this error with the tint controls, but these errors are better corrected with White Balance
(grayscale) controls normally found in service.
A thorough calibration of user controls will enhance your displays
ability to approach a degree of accuracy that is significantly better than the default factory settings. A further ISF Calibration
will be necessary for critical White Balance and other corrections.
ISF Ready Displays!
HD OTA Antenna Aiming
Imaging Science Foundation
6500 k Calibrations
PO Box 365
Welches, Oregon 97067
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