We measured the panel's actual latency:
Again we'll recall our test method:
The curve shows the different latency values for different levels of gray. A black-white alternation is shown on the curve by a point at X-axis 255, a black-gray alternation produces a point at X-axis 125, a black-gray alternation shows as 50, etc.
The official ISO latency rating specified by the manufacturer is only for black/white transitions (0/255). While the value we measured agrees with the manufacturer on this point, it's not of much value in judging the actual responsiveness of the panel in practice.
Manufacturers who use a VA panel know what to expect where latency is concerned. But clearly it's a catastrophe here. Specified at 25 ms, the X19AV went off the dial and showed as much as 135 ms in transitions in the darkest values. That kind of measurement comes as no surprise, since other monitors based on VA panels have the same fault.