GrayBar

Description

The primary version has 16 full-height vertical

 

graybars. The intensity of the bars is shown below.

 

The secondary version splits the field into a top

 

and bottom half. The bars in the bottom half of

 

the screen are in reverse order.

Black (0% Gray)

7% Gray

13% Gray

20% Gray

27% Gray

33% Gray

40% Gray

47% Gray

53% Gray

60% Gray

67% Gray

73% Gray

80% Gray

87% Gray

93% Gray

White (100% Gray)

Test

Video color tracking (color monitors)

Purpose

To check to see that a color monitor accurately

 

reproduces colors at all intensities

Method

Perform the Brightness Control Adjustment and

 

Brightness Uniformity tests first.

 

Changes in brightness from bar to bar should be

 

uniform. All of the bars should appear as an

 

untinted gray at all levels.

Test

Video Gain Linearity (monochrome monitors)

Purpose

To check the video linearity; i . e . , grayscale

 

modulation

Method

Perform the Brightness Control Adjustment and

 

Brightness Uniformity tests first.

 

Changes in brightness from bar to bar should be

 

visible and uniform.

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Quantum Data 801GC, 801GF, 801GX manual GrayBar, Brightness Uniformity tests first