Color Performance
Before I get into color testing, let's look at uniformity. After all, this is a curved display where uniformity is often an issue. While results here aren't amazing and most flat panels will produce a noticeably more even image, the GN32LD is on par with other curved displays in this metric. The edges of this display are inaccurate relative to the center, giving a slight vignette-style appearance, but I'm yet to use a curved monitor where this isn't an issue.
Default Factory Performance
Testing this monitor straight out of the box it's quite clear that Viotek has spent very little time calibrating the display to any sort of color standard. DeltaE values across our standard color accuracy tests exceed 4.0 from the factory, and the color temperature is a surprisingly warm 5894K on average, below what is required. On top of that, the "2.2 gamma" mode the panel is set to by default does not produce 2.2 gamma, but 2.0 gamma, and colors in general are left unchecked so the monitor is more saturated than it should be while displaying sRGB imagery.
Performance After OSD Control Calibration
The good news is the monitor is quite calibrateable (if that's a word), and you can make several key corrections just through the on-screen display. Using these settings here, I was able to correct the gamma issue (bizarrely gamma 2.4 gives a correct 2.2 value) and tighten up the color temperature, which improves the greyscale deltaE average to below 2.0, one of the better results I've seen just by adjusting OSD settings. Saturation and ColorChecker results improve as well.
Fully Calibrated Performance
Like with most monitors, you're not going to get the best results unless you perform a full calibration. The good news is a fully calibrated GN32LD is very accurate, with deltaEs below 1.0 indicating the monitor is well suited to color accurate work. Achieving this level of calibration only resulted in a small hit to brightness and contrast ratio, and this VA panel has a lot of headroom in those departments.
Of course I don't think many professionals would want to use a curved display for content creation, and the uniformity issues prevent the panel from being superb in terms of color accuracy. But if you want your GN32LD to be accurate, it's only a short calibration run away.