Applying an HDR signal to the CU34G2X automatically switches it to HDR mode, where you’ll find four picture options. DisplayHDR, the default, is by far the best, and it’s the only one that doesn’t apply edge enhancement to contrasting objects.
HDR Brightness and Contrast
We had hoped to see more light output from the CU34G2X in HDR mode, but it topped out at about the same level as with SDR. The result was the same whether we measured full field or window patterns. Some sort of dynamic contrast or selective overdrive of the backlight would be a great improvement here. Many of today’s HDR screens can exceed 400 nits as the other monitors here do, and we prefer to hit at least 600 nits with HDR gaming.
Fortunately, that is somewhat made up for by an excellent black level. The HDR contrast level is about the same as SDR, which isn’t ideal, but the CU34G2X still looks better than the FI27Q or EW3280U HDR monitors. Dynamic range is king, and no edge-lit monitor does it better than the Dell S3220DGF with over 18,000:1 contrast, achieved by some clever engineering of its firmware.
Grayscale, EOTF and Color
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