Three 27" IPS LCDs: UltraSharp U2711, DS-277W, And MultiSync PA271W

Out-Of-Box Performance: Color Accuracy And Gamut

We are using a Spectracal-certified X-Rite i1Pro, along with CalMan, to report color gamut and color accuracy. For those unfamiliar with the terms, color gamut refers to the range of colors that a display can reproduce, and color accuracy refers to the display's ability to output the color requested by the GPU. Typically, professionals represent these values by showing a gamut and a delta E value, which is a mathematical representation of how far apart the display's output is to the original source. The higher the delta E value, the more inaccurate the color representation. An uncalibrated delta E is largely a worthless number. Delta E is dependent on the black and white luminance levels, contrast ratio, color temperature, and target gamma.

Suppose there are two displays. One has an uncalibrated delta E value of 3.0, and the other, 2.1. It is hard to make a comparison without first calibrating the color space. It's almost like benchmarking a GeForce GTX 580 at 2560x1600 with anti-aliasing enabled against a Radeon HD 5870 at 1920x1080 without AA. Do the results of that test mean the 580 performs better? Not necessarily. Monitor calibration is to display quality what quality settings are to game benchmarks. By calibrating a display, we are able to normalize the settings and see how one display compares to another.

For this reason, we’re going to provide information in the form of a color gamut map, along with a gamut luminance chart. This gives you a better picture of how a display performs, both fresh out of the box and once it's calibrated.

Color Gamut and Accuracy

CalMan uses specific targets, which are displayed as squares in the gamut xy map. The dots are the actual measured values. Gamut luminance expresses how bright the primary and secondary colors are in relation to the source color requested by the GPU (gray bars are target values). 

Gamut CIE XY Map

Gamut Luminance

Dell U2711

DoubleSight DS-277W

Expectedly, all three IPS monitors deliver excess amounts of color compared to TN-based displays. DoubleSight's DS-277W and NEC's PA271W both produce nearly 100% of the AdobeRGB 1998 color gamut in perceptual rendering (read our printer paper benchmarks if you want an explanation of perceptual rendering). Dell seems to fall below it's 96% spec because it's approximating a white point further from 6500 K.

As we turn to color quality, all three monitors attempt to map our reference points to the equivalent hues in a larger gamut. This is a trend that we see with IPS monitors, as they try to capitalize on the superior color production capabilities that TN-based panels can't achieve. However, the luminance values are very close between each display. As we move to larger color gamuts, you'll find it difficult to distinguish differences between monitors, even with lab equipment.

  • terr281
    What monitors to review next?... As many people said in the review of the 22" TN panels from your last review, the next review should include "enthusiast available" ~23" panels. (Instead of just big box "Buy from Best Buy" models.)

    The lowest price of the three 22" TN panel monitors you reviewed was $180. A quick Newegg search shows several similar panels from names such as Acer, Asus, etc. starting at $140. (And, in the gaming, as well as office environments, 2 or 3 monitors are now more common than one single large one.)
  • nevertell
    IPS vs VA in gaming.

    Although just a regular sum up of the available 22-24 VA panels would be great.
  • Thank you for the excellent and thorough review. Perhaps next time, the new Apple 27" Thunderbolt display can be thrown into the mix. For a lot of video and photography pros like myself, the Apple display is considered to be the "standard" and I would love to see how it stacks up again the competition. Also maybe throw in a professional level Eizo display as well to show the difference between a ~$1000 display and a $3000 display.
  • The new Apple Thunderbolt 27" display - would be nice to see if it's worth the money
  • 120hz monitors lead the way

    You should review a 2560x1600 120hz IPS monitor.

    Oh wait...
    2560x1600 isn't supported at 120hz over DVI-D (dual link)
    IPS monitors can't do 120hz with today's technology



  • agnickolov
    I'd recommend the same IPS review applied on affordable 24-26" monitors that most of us would actually potentially buy. It's nice to dream about 27"+ 2560x1440, but let's get back to reality with 24" 1920x1080 and 1920x1200 (if still available) IPS monitors please. (At least until higher resolutions enter mainstream price points.)
  • crisan_tiberiu
    I have a 22" Philips LED Backlight monitor and i am very happy with it . I dont see any Philips monitors in any of your reviews, why is that? :)
  • boletus
    Nice roundup, it had me measuring what a 26" wide monitor would look like on my desk. However, you need to fix the title block in the table for the NEC monitor on the "Black And White Uniformity" page (it says Samsung S22A350H).
  • soccerdocks
    On the "Black And White Uniformity, Viewing Angles" page the 3rd table states that it is for the Samsung S22A350H when it is actually for the NEC.
  • Thank you for this comparison, very interesting reading!

    I am somewhat disappointed that 27" monitors nowadays don't use 2560*1600 panels.
    That resolution makes much more sense to me for a monitor that is not targetted at the average consumer.
    Personally I would love a 2560*1920 (or 2048) screen @ 120Hz, but if I understand correctly link speed becomes an issue here.

    Why is it that displays for mobile phones are increasing in pixel density, but desktop displays don't improve in this regard?

    For a next review I would really like to get a better understanding of (high-resolution) 120Hz monitors. What are the (dis)advantages of 120Hz for regular/2D usage, etc...