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The X34 OLED is certified for DisplayHDR 400 True Black, but it could earn a 600-nit badge if it wished. It is one of the brightest 34-inch OLED 21:9 monitors currently available. It supports HDR10 signals with an automatic switch.
HDR Brightness and Contrast
Only the very expensive PG34WCDM is brighter than the X34 OLED, and not by much. 663 nits is very bright and well ahead of the rest, which are around 450 nits. The AOC is dimmer because it doesn’t have variable brightness for HDR like the others. The net effect is that highlights are very bold which makes the X34 OLED more textural and three-dimensional than dimmer screens. Acer rates it at 1,300 nits for a 1.5% window, and there is no reason to doubt that claim. I measured a 25% window for this test.
Grayscale, EOTF and Color
I could see a faint green tint in my X34 OLED’s HDR grayscale pattern. There is no means of adjustment here, but the impact on content was minimal. The EOTF is a bit wonky with dark tracking below 20% and a bit too much brightness from 30 to 70% where the tone map transition is. In practice, this obscures the deepest shadow detail, but midtones and highlights are not affected.
The color charts are textbook in appearance. All color points are on target or just a tad oversaturated. The X34 OLED looks plenty vivid without any need to push color like so many other HDR monitors do. This is excellent performance. The BT.2020 test looks similar with on-point performance until the panel runs out of color at 83% red, 75% green and 95% blue.
Test Takeaway: Despite a slightly green grayscale and a skewed EOTF, the X34 OLED has a solid HDR image with very accurate color. It’s very bright and textural thanks to its high peak level, which more than mitigates any deficiencies. I wish there were a Quantum Dot layer for more color, but even so, it looks impressive.
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oofdragon Great colors AFTER calibration isn't a pro, it's a con. At this price it should come calibrated and ready to goReply -
thestryker Missing the 800R curve from the cons which even LG seems to be tacitly admitting was a mistake since the new UW panel announced has ditched it for 1500R.Reply -
sauve.richard Reply
I'm with you on that. I was really eyeing up an LG Ultragear 39 inch uw oled, it looked perfect, then I saw the 800R curve and it was an instant deal breaker for me.thestryker said:Missing the 800R curve from the cons which even LG seems to be tacitly admitting was a mistake since the new UW panel announced has ditched it for 1500R.