Why you can trust Tom's Hardware Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you. Find out more about how we test.
To learn about our HDR testing, see our breakdown of how we test PC monitors.
When the S2721DGF senses an HDR10 signal, it automatically switches to HDR mode. There are four image presets available, plus control of the contrast slider.
HDR Brightness & Contrast
Dell rates the S2721DGF at 400 nits in HDR mode, but we couldn’t quite get there in our tests. We measured both 100% and 10% window patterns and got the same result.
But once we completed the tests, we were glad to see that Dell has included dynamic contrast. The 0.08-nit black level is in VA territory, with resulting contrast near 5,000:1. This puts the S2721DGF in a small group of edge backlight HDR monitors that look good showing HDR content. Remember when we said earlier, “you get what you pay for?” This is a perfect example.
Grayscale, EOTF & Color
The S2721DGF’s lack of HDR calibration control is not a hindrance to its HDR image accuracy. The grayscale test above shows a slightly visible blue error in the brightest steps that's hard to see in actual content. What is more impressive is the near-flawless EOTF luminance tracking. Except for a slightly soft transition to tone-mapping at 65%, the test follows the spec perfectly. This is the principal reason for the S2721DGF’s excellent HDR image.
The color test reveals similarly high accuracy. Every DCI-P3 color target is on or near the right spot, and inner saturations are a little over. This adds to the S2721DGF’s vibrance in HDR mode. If HDR gaming is your thing, you’ll have to spend quite a bit more money to beat this level of performance.
Current page: HDR PerformancePrev Page Grayscale, Gamma and Color Next Page Viewing Angles, Uniformity, Response and Lag
Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors.