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VP400 Series Video Pro
Form7343A
Operation Manual
30
Window1, Window2
Pattern Description
:
The Window1 and Window2 patterns are a centered white window on a black background.
Luminance levels of Window1 and Window2 are independently adjustable from 100 IRE to 0
IRE in 1 IRE steps. Each window pattern includes pluge level bars at +4% and –4% to the left of
the white window.
Pattern Usage
:
Use the white window to measure chromaticity of
a display device. This pattern is preferable to
using a full field white raster since the window
pattern more closely duplicates the average
picture level (APL) of typical program material
and doesn’t unnaturally stress display circuits.
When adjusting grayscale tracking, one window
can be set for low luminance and the other
window set for high luminance to quickly switch
between adjusting cutoff controls (low luminance)
and drive controls (high luminance).
SplitGray
Pattern Description:
The SplitGray pattern consists of an upper and lower section. The top and bottom section
contains bars that vary in level from black to white in 17 steps. The top section progresses from
black to white in 17 steps from left to right on a display. The bottom section progresses from
white to black in 17 steps from left to right on a display. Since the progression from black to
white is opposite on the top and bottom, they provide a mirror image grayscale level meeting in
the middle at 50%.
Pattern Usage:
Use the SplitGray pattern to visually analyze the
grayscale tracking performance of a display. The
pattern provides 15 individual steps of gray. Poor
performance is seen when a primary color tint
(red, green, or blue) is observed within the black,
gray or white bars of the pattern. Tinting is often
prevalent at the bright or dark end of the pattern.
This pattern is also useful for adjusting grayscale
tracking by eye, when a color analyzer is not
available. Adjust the display cutoff/bias controls for a neutral dark gray tone at the dark end of
the pattern. Adjust the display drive/gain controls for a neutral bright gray tone at the bright end
of the pattern.