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Our HDR benchmarking uses Portrait Displays’ Calman software. To learn about our HDR testing, see our breakdown of how we test PC monitors.
The Zion Pro is compatible with HDR10 signals and will switch automatically if HDR Auto mode is engaged. There are no image controls available for HDR content, but I found the panel accurate enough for a quality HDR presentation.
HDR Brightness and Contrast
Zion’s Kickstarter site lists 400 nits as the peak output, but I could not achieve this figure. HDR brightness is slightly lower than SDR at a maximum of 231.3684 nits. This doesn’t harm image quality as blacks are still infinitely low. Contrast is just as good as any other OLED and far beyond anything possible from an LCD panel. The only scenario where you’ll want greater brightness is in sunlit rooms or outdoors. A little more output would be welcome, given the Zion Pro’s portable form factor. But it still looks amazing in my office.
Grayscale, EOTF and Color
The Zion Pro’s HDR grayscale tracking is close to what I measured for SDR. It was slightly warm in the middle and higher steps but generally without visible errors. There are no adjustments available, so this is a good thing. The EOTF tracking is a bit dark and hits the transition point about 15% too late. What this means is that some HDR video content will look too dark. However, it depends on the accuracy of the original material. This is where an adjustment would be welcome. Luckily, most HDR-capable games have calibration controls built into their menus so you can tweak the image to suit the display.
