How To Interpret The Graph
The calibration gives us a DeltaE graph of the monitors. This value corresponds to the measured difference between the requested color and the color actually reproduced. A DeltaE less than or equal to 1 represents a perfect calibration: there is no perceptible difference between the original color and the reproduced one. Starting at DeltaE = 3, the human eye can detect the difference in shade.
On the X-axis: the values go from black (0) to white (100). On the Y-axis is the DeltaE.
Applied to the graph of our Prophetview 920 Pro, this means that:
- DeltaE < 2 = 94% of the colors displayed, from dark gray to white, are correct.
- DeltaE < 1 = 76% of the colors are reproduced perfectly.
- DeltaE > 3 = 4% of the colors displayed are not accurate. This is the case mostly with dark colors on TFT monitors.
This test also shows:
- Contrast level with the calibration adjustments.
- Black depth, with a measurement of black brightness displayed with the same adjustments.
- Brightness under test conditions.
So, using these results, you can judge the "static" quality of the monitors - that is, their ability to display still images precisely. But what about latency?
Measuring Latency
The System
The complete system for measuring latency consists of:
- An optical sensor that converts light intensity into voltage.
- A linear laboratory power supply to power the sensor.
- A digital oscilloscope.
- Stimulation software.
Since this is a specially developed system, we should describe how it operates and performs, in order to rule out any doubts as to the validity of our measurements.