Sencore VideoPro VP400 Series, Руководство по эксплуатации

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VP400 Series Video Pro Form7343A Operation Manual
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SMPTE Bar
Pattern Description :
The upper two-thirds of the pattern consists of seven equal-width vertical bars, with 75% white
(gray) at left, followed by three primary and three secondary colors. Color bars are at 100%
saturation with 75% amplitude. Just below these bars is a section of short bars containing the
blues complement color for each of the large bars containing blue. Under those color bars
containing no blue (yellow, green, and red), the short bar is black. The bottom one-fifth of the
pattern consists of the following seven signals, starting from left to right; 1) -I, 2) 100% white, 3)
-Q, 4) black, 5) slightly blacker than black (4 IRE for NTSC, -4 IRE for other formats), 6) black,
7) slightly whiter than black (11 IRE for NTSC, +4 IRE for other formats).
Pattern Usage :
Use to adjust color and hue through a blue filter
with composite, S-video, or YPbPr signal inputs.
While viewing the pattern through a blue filter,
adjust the color control for equal brightness
white/blue bars. Adjust the hue control for equal
brightness cyan/magenta bars.
Note: RGB input signals aren’t processed through
a color decoder, thus no color adjustments with an
RGB input signal; also, YPbPr inputs may not
have both color and hue adjustments.
Also, use this pattern to adjust a display’s black
level at a medium APL. With the brightness (black level) control first adjusted to a slightly
higher than normal setting, reduce the brightness control setting until the slightly blacker than
black bar (under the large cyan bar) and the black bar (under the large red bar) are both just
black. The slightly whiter than black bar (under the large blue bar) should still be slightly visible.
Staircase
Pattern Description :
Eleven equal-width vertical bars step from black at the left (7.5 IRE for NTSC, 0 IRE for all
other formats) to 100 IRE white at the right.
Pattern Usage :
The Staircase pattern is useful for visually
checking grayscale tracking performance of a
display. Poor performance is seen as a
primary color tint (red, green, or blue),
especially at the bright or dark end of the
pattern. The 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. The pattern is useful as a
reference input signal when troubleshooting
luminance or R, G, B amplifier problems
within a display device using an oscilloscope.