Selecting a video test pattern, Ns in six categories (see – Extron Electronics VTG 300_300R User Guide Rev. E User Manual

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Selecting a Video Test Pattern

Pressing the Test Patterns button will determine what category of test pattern to display.
The signal range and/or the output rate also determine the actual test pattern.

Figure 14

provides a description of the available test patterns.

White Field - 80% window

Color Bars

SMPTE Color Bars

Multiburst

Crosshatch - 32 x 18

Crosshatch - 32 x 24

Alternating Pixels

H Pattern - white on black

Grayscale - 32-level split

EBU Color Bars

Grayscale - ramp

16:9 Static and Dynamic Convergence -
This pattern can be used to set projector
focus and geometry. For CRT projectors,
this pattern is for examining and adjusting
both static and dynamic convergence, so
that the red, green, and blue video signals
are aligned throughout the image. This
pattern is also useful for evaluating some
optical qualities of projector lenses, such as
chromatic aberration.

Static and Dynamic Convergence -
This pattern can be used to set projector
focus and geometry. For CRT projectors,
this pattern is for examining and adjusting
both static and dynamic convergence, so
that the red, green, and blue video signals
are aligned throughout the image. This
pattern is also useful for evaluating some
optical qualities of projector lenses, such as
chromatic aberration.

SMPTE with PLUGE -
For NTSC video equipment, the SMPTE
color bars are used to set up tint and color,
while the PLUGE video pattern is used for
adjusting brightness and contrast. Color
levels are set to 75% (75 IRE).

EBU -
The EBU color bars are primarily used to set
up color for PAL video equipment.

8-color split bars -
This pattern is used for testing all of the
video color channels and setting video drive
levels. It is also used to check low frequency
crosstalk between the red, green, and blue
color channels. Color levels are set to
100% (100 IRE).

Video level tracking and video gain linearity -
This pattern is used for setting and assessing
grayscale tracking, and evaluating contrast
linearity on displays. The pattern consists of
two opposing rows of 32 stepped bars of gray
between the lowest and highest levels.

Pixel bit depth -
This pattern is used to evaluate the performance
of a display or video processor on the basis of its
pixel bit depth capability. The pattern should
appear to be smooth, with no contouring or
stepping.

Resolution/High Frequency Response -
This pattern can be used to check display
focus or video pulse response on PC, video,
HDTV, and 16:9 HR equipment.

Bandwidth performance -
This pattern, consisting of sine wave bursts of
increasing frequency, tests bandwidth
performance over the NTSC and PAL video
channel.

Flat Field (Full Field)

White field uniformity -
This pattern is used to evaluate white field
uniformity.

Monitor performance -
This "one pixel on, one pixel off" pattern is used
for assessing the performance of high
resolution monitors and projectors, EMI testing
for worst case radiation, and pixel clocking and
pixel phasing adjustments on a digital display.

Color balance adjustment -
A window at 80% (80 IRE) video level,
surrounded by black, is used in fine tuning
the color balance (or grayscale) of a display
with the aid of a color analyzer. The gain
(or drive) setting is fine tuned for each of
the red, green, and/or blue color
adjustments.

White Field - 20% window

Color balance adjustment -
A window at 20% (20 IRE) video level,
surrounded by black, is used in fine tuning
the color balance (or grayscale) of a display
with the aid of a color analyzer. The bias
(or offset) setting is fine tuned for each of
the red, green, and/or blue color
adjustments.

Figure 14.

VTG 300/300R Test Patterns

VTG 300/300R • Operation

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