For the uniformity, or the evenness of the backlight of the lcd, we measure the brightness of white and black in 15 zones and compare the value of the middle of the panel with the highest measured values as well as with the average of the measurements. This results in a percentage. Upwards of 80% is good, from 85% we are enthusiastic and anything above 90% makes us extremely enthusiastic.
The Dell U3417W that we compare this monitor with standard has an activated uniformity compensation, and this shows. Ultrawide monitors are not the best when it comes to uniformity, but the Dell shows that there is quite a bit possible. The ASUS MX34VQ that we discuss in this review does not have that functionality, which results in a lower score. Nevertheless it performs quite well, especially if you consider that the absolute differences are a lot smaller with black and therefore stand out less. With white the values are more than acceptable.
Looking at the sub measurements in 15 zones, we see a very limited variation with black in absolute sense: the lowest value is 0.06 cd/m², the highest is 0.09 at the top left. With white we see slightly more variation, when the middle is set to 150 cd/m² the rest lacks about 10 nits behind and on the far left and right the brightness is lower still. This results in varying contrast values, that end up at 1519:1 in the worst case and 2217:1 in the best case. This is quite a difference. Because of this, the colour temperature differs quite a lot, with values just below 7000 at the top right and over 7300 at the left side. We also see values higher than 3 with the colour fault comparison, with a high of 5.1 at the top left. This is something to bear in mind for image processing.
Bear in mind that the colour in the boxes with the uniformity of black, white and the contrast is related to the results of the measurements for that model; not to the absolute values.
- As for black: the lower the measured value, the better (=greener); if the value is higher this means worse (=redder).
- For white the colour coding is different, because there we set a specific brightness of 150 cd/m². That is why values that are closer to this setting green, values that are further away become red – the more they deviate the redder they are.
- As far as contrast is concerned, the highest contrast is green, the lowest is red – the values in between are marked by these colours. Greener is better, redder is worse. We emphasize again that these values are relative: a contrast of 1702:1 is excellent, but if the highest measured contrast is 2581:1, the former value is still marked in red.
- With the colour temperature the measurements are bluer the lower they are, yellower the higher they are.
- Last but not least the colour deviation: here you see a number for the DeltaE value in the boxes, where values below three are barely noticeable with the naked eye. The colour of the boxes shows the colour deviation of gray.