The AW3821DW switches automatically to HDR mode once you apply an HDR10 signal. All picture presets are still available, and they all make a visible difference in color and contrast. Standard works reasonably well, but the best HDR image results from a calibration in the Custom Color mode. Luckily, the same RGB settings work for both SDR and HDR.
HDR Brightness & Contrast
The AW3821DW is rated for 600 nits but we managed a peak reading of over 724 nits. We had to measure a window pattern to achieve this, and the level quickly dropped once we displayed a full pattern. Variable Backlight is locked on for HDR signals, but you can still pick from the three levels. Mode 0 provides the fastest switching and the greatest dynamic range.
Black levels are super low because the backlight is nearly turned off when a 0% signal is input. That results in an HDR static value of over 60,208:1, impressive performance. As an edge backlit monitor, its HDR image isn’t as dramatically improved as a zone dimming screen with the same test results, but the Variable Backlight feature definitely has a positive impact on HDR material.
Grayscale, EOTF & Color
The AW3821DW is one of the few HDR monitors that allows calibration in HDR mode. The first and third charts above show the fixed Standard mode. Grayscale runs a little blue as brightness increases, but the errors are minor. The luminance curve is a bit skewed, thanks to Variable Backlight. Using the RGB settings from SDR in the Custom Color mode improves grayscale tracking to where the blue errors only occur after the tone-map transition point. That means you’ll almost never see them in actual content.
Color tracking is solid with slight oversaturation of all inner primary and secondary targets. This is typical of the HDR monitors we’ve tested. Though not strictly accurate, it provides a nice bit of extra punch and helps differentiate HDR content from SDR. Our calibration (see our recommended settings on page 1) boosts hue accuracy and shows a positive visual effect.