Measurements

NEC advertises 400 cd/m2 brightness and 800:1 contrast ratio.

This review provides a rare possibility to compare 2490 condition over it lifespan. This unit has now over 6500 hours in use.
Although at the beginning of it's career the testing methodology was not as detailed as we practise it now, it's still possible to compare some data.

This unit has revision 2B.

Note: For all measurements Contrast control is left at its factory default - 50%.

Initial measurements 6500 hours ago:
White - 360 cd/m2
Black - 0.46 cd/m2
CR - 783:1
Measurements always fluctuate a little, so we can say that CR was fluctuated around advertised 8oo:1 - it's excellent for IPS today as well as 2 years ago.
Brightness did not achieve 400 cd/m2 and that was just good!
400 cd/m2 is about twice as much as you might need on your monitor.
Now you know that 2490 has three level of brightness control.
At the first level of brightness with Brightness control set to zero 6500 hours ago:
White - 160 cd/m2 (This is medium to high for a regular monitor. For 2490 this is not a problem considering other brightness modes and the variety of calibration options.)
Black - 0.21 cd/m2 (At that time it was an outstanding record for an IPS-based monitor).

What do we see after 6500 hours?
We see that the NEC 2490 is getting better as it is getting older!
Maximal brightness has slided down to much healthier 322 cd/m2 leaving plenty of room for further reduction.
Minimal black dropped below 0.17 cd/m2.
It takes the 2490 18-19 min to reach the full brightness.
The monitor continues to retain its original high contrast ratio near 800:1