Author Topic: Dell S2719DGF Review: Matte 27" 2560x1440 144hz AUO TN Panel with AMD Free-Sync  (Read 8244 times)

NCX

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Preset Color Accuracy

Dell S2719DGF Preset Chart by Deepinthesky Teslastorm, on Flickr

I measured the preset color accuracy of the S2719DGF with my Spectracal C6 HDR2000 colorimeter and the free HCFR calibration program which I also use to calibrate displays as best as possible with only their menu settings.  The HDMI 2.0 port is supposed to support 144hz according to the manual (page 15), but only 60hz showed up in the Nvidia Control panel when connected to my GTX 980 ti with an HDMI 2.0 cable.  All TN panels colors and shades are uneven from top to bottom since all TN panels suffer from vertical gamma shift: colors and shades are too dark in the top quarter if the gamma is 2.2 in the center, and colors and shades are washed out in the bottom half since the gamma drops the further away from the top of the panel colors and shades are.

The image quality offered by the S2719DGF is significantly better when using the HDMI input since the preset gamma is significantly higher, but still too low which results in washed out image quality.  The S2719DGF is basically the same at 60hz and 144hz while many 144hz 1080p AUO TN panels suffer from contrast, gamma and uniformity loss when set to 144hz, including the Acer XF240H and Viewsonic XG2402 I recently reviewed.  When the Overclock setting is enabled the S2719DGF can be set to 155hz, but doing so causes the gamma to drop a bit which further washed out the already washed out colors.

The contrast or perceived black depth is very poor by default since the S2719DGF has a matte black bezel on the sides and top which reduces the perceived black depth, and because the brightness is set to 75 out of the box which measures at 280cdm/2 which is way to bright for my single 2200 lumen light source, a 2200 lumen 5000K color temperature LED light made by Anmien.  The perceived black depth or contrast is average once I reduced the brightness to a suitable level (32 in the menu for 140cdm/2) for my room lighting since the contrast is only slightly above average (800:1), and because black in dark content looks light next to the black bezel.
 
HCFR Gray Scale Delta E:
Spoiler (hover to show)

HCFR Gamma Measurements:
Spoiler (hover to show)

At 60hz when connected via Displayport the S2719DGF's gamma is fairly linear and ranges between 1.95 (lowest measurement) and 2.03 (highest measurement), 1.944 and 1.995 at 144h-155hz (tiny drop), and 2.033 to 2.284 when connected via HDMI at 60hz.   The gamma is marginally lower at 144 and 155hz (155hz unlocked by activating the Overclock option the menu), but the drop is too small to be perceivable.  Regardless of which input is used the S2719DGF looks very washed out and dull, abd the preset gamma accuracy is significantly worse than most of the 120-144hz 1080p TN panels I have tested since 2010.  Sadly the Dark Stabilizer setting, which is the only gamma setting the monitor has, is useless since it further lowers the gamma.

HCFR RGB Levels Measurements:
Spoiler (hover to show)

The preset RGB Level accuracy of both the S2719DGF is excellent, as well as superior to all three of the 144-165hz 1440p AHVA (marketed as IPS) panels (Acer XB271HU, Asus PG279Q and Viewsonic XG2703-GS) I tested.  All three 144hz AHVA panels suffered from obvious preset green and yellow tints to browns, greys and whites while both Dell monitors are very neutral, or free from an obvious preset color dominance.  It's such a shame that the neutral preset color balance offered by the S2719DGF is ruined by the very low preset gamma.

HCFR Color Gamut Measurements or HDTV/REC 709 Color Space Coverage:
Spoiler (hover to show)

As mentioned above, the S2719DGF's color gamut significantly over and under-saturates some colors compared to both the HDTV/REC 709 and sRGB color space.  The top left side of the triangle (HDTV/REC 709 color gamut) falls short resulting in the under-saturation of blue and medium to dark greens. Medium to light greens, yellows, oranges and some reds are all over-saturated, a phenomenon typical of AUO panels, including both their 27" 2560x1440 and 32" 3840x2160 AHVA (more balanced or pure) panels which also over-saturate the same colors resulting in green and yellow tints to browns, greys and whites, even after calibration. 

HCFR Color Temperature Measurements:
Spoiler (hover to show)

The balanced and linear RGB Levels versus the HDTV/REC 709 and sRGB standards results in nearly linear 6500k color temperature.

Overall the S2719DGF offers passable color accuracy, which could have been outstanding if the preset gamma was not so low, and results in very dull and washed out image quality since the monitor lacks gamma settings which can be used to raise it.  The preset gamma is significantly lower than the S2716DG, but it costs significantly more.  The preset RGB level accuracy and white purity is outstanding and superior to most monitors under 800$ US, as well as most monitors I've tested aside from the BenQ BL3201PH and Samsung S27D850T I tested in 2014 and 2015.  Two major improvements offered by the S2719DGF versus most TN panels are the lack of horrific banding when viewing this Dawn Engine image I sourced from this Reddit post, and the matte coating which is completely grain and sparkle free unlike most TN panels.
« Last Edit: November 18, 2018, 10:16:25 pm by NCX »