Sharp PN-K321 32-Inch Ultra HD Monitor Review: More 4K!

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.

Results: Grayscale Tracking And Gamma Response

Our grayscale and gamma tests are described in detail here.

Out of its box, the PN-K321’s white balance runs a bit cool, especially above the 50-percent brightness level. This is a decent result and you could use the monitor uncalibrated so long as you're able to live with a slight blue tint to mid- and high-level whites. We tried the sRGB mode, which locks out color adjustments, and recorded nearly identical results. So, there’s no gain to be had there.

Only an instrumented calibration will produce the above result. You’re looking at perfection. Thanks to the inclusion of low-range RGB sliders, we were able to fix all the grayscale errors. It really doesn’t get better.

Here is our comparison group:

Thanks to solid numbers below 60-percent brightness, the PN-K321 posts a good out-of-the-box average error of 2.88 Delta E. The fact that our winner, Asus’ PQ321Q, uses the same panel demonstrates that a monitor is more than simply the sum of its parts. Engineering and care in manufacturing make a visible and measurable difference.

The calibrated grayscale error falls squarely into the realm populated by high-end professional displays. It’s unfortunate that neither the Sharp nor the Asus have a wide-gamut option. Again, this is pretty much perfect grayscale performance.

Gamma Response

We observed some interesting results in the gamma tests, so we’re showing you the traces for the Standard, 2.2 and 2.4 presets.

The standard gamma setting produces a chart similar to what you’d see when dynamic contrast is in use. The lower levels are made darker and the higher ones lighter to increase perceived depth at the expense of poor detail.

Selecting the 2.2 gamma preset tightens tracking considerably. It’s the same result you’ll see if you choose the sRGB color mode, although doing that locks out the RGB sliders. Aside from minor dips at 10 and 90 percent, this is an excellent chart.

Since the 2.2 preset runs a tad low (too bright), we wanted to try 2.4. It changes the tracking a little and makes things a little darker, but only subtly. It also comes closer to BT.1886. We would use the setting for movies and some games, while sticking to 2.2 for productivity and graphics work.

Here is our comparison group again:

None of the displays in the group have any significant gamma issues. All of them track pretty well with only small variations that can’t be seen with anything but our meter.

We calculate gamma deviation by simply expressing the difference from 2.2 as a percentage.

The 2.2 gamma setting’s result is a tad below 2.2, landing at 2.11. Aside from the 10- and 90-percent levels, the rest of the trace is almost on the line. Again, you won’t really see any problems with actual content on any of these monitors.

Christian Eberle
Contributing Editor

Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors. Christian began his obsession with tech when he built his first PC in 1991, a 286 running DOS 3.0 at a blazing 12MHz. In 2006, he undertook training from the Imaging Science Foundation in video calibration and testing and thus started a passion for precise imaging that persists to this day. He is also a professional musician with a degree from the New England Conservatory as a classical bassoonist which he used to good effect as a performer with the West Point Army Band from 1987 to 2013. He enjoys watching movies and listening to high-end audio in his custom-built home theater and can be seen riding trails near his home on a race-ready ICE VTX recumbent trike. Christian enjoys the endless summer in Florida where he lives with his wife and Chihuahua and plays with orchestras around the state.

  • cknobman
    Over $3000


    Get this BS under $1000 or dont even release it.
  • Kridian
    Yep, they're out of their GD minds!
  • 10tacle
    I'd start *thinking* about buying one of these at a $1500 price point, get more serious at a $1200 price point, and pull the trigger at a $1000 price point...AND when it's a 120Hz panel.
  • InvalidError
    14481231 said:
    Over $3000


    Get this BS under $1000 or dont even release it.
    Give it some time. Display manufacturers like gouging fat wallets while they can to recover some of their R&D costs while production volumes are still low and their products are still different enough to justify higher margins over models aiming for the bargain basement.
  • loki1944
    Maybe by the time single GPUs can run games at 60fps on 4K prices will be reasonable, because right now holy cow. Sticking with my 1080p and 1440p monitors for now.
  • NightshadeRC
    I got 2 of the Samsung 4k 60hz monitors about 3 months ago and they were only $349 each. Much better than the 1080p for $150-$200 and 1440p was another couple of hundred more (in Australia, tech tends to cost a bit more).
    It's won't be long before 4k TN gets more popular
  • jfkeenan
    Cost is one thing, but why aren't they using HDMI 2.0? My GTX 980 is begging for a 4K 60hz monitor.
  • rantoc
    Got an Dell 3214 and the "split screen" (many don't know this fact about the current 4k 1.2 DP driven displays running at 60hz but in order for DP1.2 to show 4k @ 60 hz the screen is virtually split into two screens over the interface and then combined) issue, many have all kind problems with this including only picture on one screen, different resolutions on one half or all kind of wake from sleep issues.

    My advice - Wait for DP1.3 that can handle 4k@60hz properly before considering an 4k screen and that is a shame - the resolution and picture clarity on the Dell UP3214Q is an enormous breakthrough - The issues however are so severe i'm not even using it! So much for a 2000$ monitor =/
  • beetlejuicegr
    I want a 24inch 4k display at 300$. Till then not buying! ^^
  • cypeq
    That's TV not monitor my TV is this big.