Checking Rgb Gamut - Tektronix WFM8200 User Manual

Checking Gamut

Checking RGB Gamut

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Arrowhead – Use to detect composite gamut errors, without employing a
composite encoder.
Spearhead – Use to detect RGB gamut errors.
4. Press the GAMUT button to dismiss the pop-up menu.
5. Press the CONFIG button and select Gamut Thresholds.
6. Set the thresholds as desired.
The Diamond and Spearhead displays effectively show how the R, G, and B
signals relate. The Diamond display is a good tool for detecting gamut errors.
Spearhead requires Option PROD.
To form the Diamond display, the instrument converts the Y, P
recovered from the serial signal to R, G, and B. To predictably display all three
components, they must lie between peak white, 700 mV, and black, 0 V.
For a signal to be in gamut, all signal vectors must lie within the G-B and G-R
diamonds. Conversely, if a signal vector extends outside the diamond, it is out
of gamut. The direction of an excursion out of gamut indicates which signal is
excessive. Errors in green amplitude affect both diamonds equally, while blue
amplitude errors affect only the top diamond and red errors affect only the bottom
diamond. (See Figure 59.)
Figure 59: Diamond display plot
WFM8200 and WFM8300 Waveform Monitors
and P components
b, r