Quantum Data 881 User Manual page 988

Video test instrument
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Appendix B Image Reference
960
High contrast resolution
All the 0 and 100% level stripes in all the resolution patches should be separate and
distinct.
Low contrast resolution and noise
All the mid-level 2 on - 2 off stripes in all the resolution patches should be visible and
distinct. This is a sensitive test for noise in the display's video amplifiers.
Quick gamma check
The average brightness level of the small gamma dither box should match the brightness
of the larger surrounding box. This is a visual check to see if the display's gamma
correction is producing the correct mid-level response.
Video gain linearity and gamma
The individual grayscale boxes all should be at their indicated levels. A small aperture
photometer is usually required to get accurate and repeatable readings.
Contrast and brightness check
On a display with properly adjusted brightness and contrast controls, both the 5% and
95% contrast boxes should be clearly visible inside their larger surrounding 0% and 100%
boxes.
Video amplifier stability
The two black-and-white windows should show sharp transitions between the smaller box
and the surrounding window. Streaking may be an indication of undershoot or overshoot
while ghost images may indicate a ringing problem.
Excessive overscan and off-center alignment
The entire border should be clearly visible on the face of the tube and not be hidden by the
edge of the glass or by any bezel.
Interlace flicker

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