Tektronix WFM2200A, Руководство пользователя

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To set up gamut checks
1. Connect a video signal to an SDI input on the rear panel.
2. Select a tile in which to view the Gamut Display and press and hold the
GAMUT button.
3. In the Gamut pop-up menu, select from the following gamut display types:
■ Diamond – Use to detect, isolate, and correct RGB component gamut
errors. See
Checking RGB gamut on page 202.
■ Split Diamond – Use to reveal hard-to-find black gamut errors.
■ Arrowhead – Use to detect composite gamut errors, without employing a
composite encoder.
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.
Checking RGB gamut
The Diamond display effectively shows how the R, G, and B signals relate and is
a good tool for detecting gamut errors.
To form the Diamond display, the instrument converts the Y, P
b,
and P
r
components 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 following image.)
Checking gamut
202 WFM2300 and WFM2200A Waveform Monitors User Manual