Ensemble Designs 7405 HD Test Signal Generator - Manual (Page 18)

A.2 TEST PATTERN DESCRIPTIONS
Bars Test Patterns
All of the color bar patterns include peak white, black, and the six vector colors (yellow,
cyan, green, magenta, red, and blue), either at 75% or 100%.
Split Field Bars
Pluge and level reference is added to the color bars to make a split field. The pluge
is used to adjust monitor brightness and to check for clipping in digital systems.
The pluge includes +/- 2 IRE levels around black, four luminance steps, and a 5
IRE "top hat" above peak white.
In composite systems, monitor brightness can be adjusted using the +/- 2 IRE
levels around black by making the right-most level disappear in the adjacent black
while making the left-most level just visible.
In digital systems, the number of steps of dynamic range is limited by the number
of bits used to represent them. Black is represented by 040h and white is repre-
sented by 3ACh. If clipping occurs in the digital processing of a signal, the "top
hat" and/or the 2 IRE superblack level can be clip off.
Full Field Bars
Full field bars is sometimes called simple bars as it does not include anything else.
It is color bars from the top of the field to the bottom.
100% is usually used for component signals as the amplitude of the Cb and Cr
signals is the same as the Y signal. A waveform monitor can be used to align Y, Cb,
and Cr gain.
75% is more commonly used with composite--when viewed on a waveform monitor,
the chroma yellow and cyan envelope is lined up with the peak white level. As
such, a waveform monitor can be used to align luminance and chrominance gain,
and a vector display can be used to align chroma phase.
Mon Align (SMPTE Color Bars)
SMPTE Color Bars has a reverse sequence of bars to help adjust monitor levels on
monitors that provide blue only displays. Hue can be aligned by balancing the
chroma bars, and chroma can be set by matching the chroma bars to the white
bars. It also includes pluge.
Mon Align
In addition to pluge, SMPTE Color Bars includes a reverse sequence of bars.
The reverse sequence helps adjust monitor levels on monitors that provide blue
only displays. Hue can be aligned by balancing the chroma bars, and chroma can
be set by matching the chroma bars to the white bars.
7405-A2
Model 7405 HD Test Signal Generator