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Black And White Uniformity, Viewing Angles

Three 27" IPS LCDs: UltraSharp U2711, DS-277W, And MultiSync PA271W
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Another measurable aspect of panel performance is brightness uniformity. Most manufacturers calibrate displays based on the center point of the screen. However, every area of the screen behaves differently. Sometimes you can get better performance in one specific region. As a result, we added a nine-point black and white luminance test to measure the performance of each monitor's panel.

Dell UltraSharp U2711
White Luminance cd/m^2
181.2630180.5343142.577
195.8545200.0100160.9077
200.0313202.1060172.9605
Black Luminance cd/m^2
0.2737
0.1950
0.2309
0.3024
0.2726
0.1787
0.3727
0.2580
0.2184


The U2711 appears to have slightly poor white luminance in the upper right-hand corner and poor black luminance in the bottom left-hand corner.

DoubleSight DS-277W
White Luminance cd/m^2
187.7542177.9022162.4172
194.8163199.1000166.1605
200.4431202.9104165.4207
Black Luminance cd/m^2
0.79400.84870.7247
0.79600.78120.7308
0.90600.89920.8512


Black luminance is fairly even, though this doesn't alleviate the poor contrast issues cited earlier. The DS-277W demonstrate less uniformity with respect to white luminance, as there's a noticeable deficit on the right-hand side. Color production isn't affected when you view the display at wider angles, but the lack of white uniformity makes the right side seem slightly less vibrant than the left side.

NEC PA271W
White Luminance cd/m^2
186.8910190.8966173.7275
193.0134201.6654185.0052
186.3268196.0234184.4747
Black Luminance cd/m^2
0.19970.17100.4115
0.18140.20060.1669
0.35190.27610.1792


We are able to calibrate the center of the screen to 200 cd/m2, but this offsets other regions, as white uniformity radiates outward from the center. Black luminance seems to behave differently. In the upper right- and bottom-left corners, the PA271W struggles to produce deep blacks. But this is only apparent if you're viewing the monitor at extreme angles.

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  • -2 Hide
    terr281 , August 11, 2011 5:17 AM
    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.)
  • 1 Hide
    nevertell , August 11, 2011 5:27 AM
    IPS vs VA in gaming.

    Although just a regular sum up of the available 22-24 VA panels would be great.
  • 2 Hide
    Anonymous , August 11, 2011 5:49 AM
    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.
  • 4 Hide
    Anonymous , August 11, 2011 5:57 AM
    The new Apple Thunderbolt 27" display - would be nice to see if it's worth the money
  • 8 Hide
    Anonymous , August 11, 2011 6:03 AM
    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

    Bummer!

    :( 

    F
  • 5 Hide
    agnickolov , August 11, 2011 6:16 AM
    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.)
  • 0 Hide
    crisan_tiberiu , August 11, 2011 7:04 AM
    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? :) 
  • 0 Hide
    boletus , August 11, 2011 7:25 AM
    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).
  • 0 Hide
    soccerdocks , August 11, 2011 7:38 AM
    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.
  • 1 Hide
    Anonymous , August 11, 2011 8:29 AM
    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...
  • 0 Hide
    Jax69 , August 11, 2011 8:59 AM
    wait for Samsung's PLS and other iterations of the panel from different brands.
  • -3 Hide
    pirateboy , August 11, 2011 9:47 AM
    please review Asus PA246Q and any other 24 inch 16:10 screens you can get your hands on...please don't review anymore 16:9 screens
  • 0 Hide
    bavman , August 11, 2011 12:40 PM
    I wish i could afford one of these beautiful monitors =(
  • 0 Hide
    jacobdrj , August 11, 2011 1:14 PM
    30" Dell IPS, Apple Cinima Display, IMac 27/30" display, TV's for use as TV monitors. 3d Monitors. Quad LCD monitors (RGB+Yellow)... Projectors, including lag time...

    CNet used to do stuff like this, so did PC Mag. They stopped. Bothers me. I have to rely totally on Amazon/Newegg/TigerDirect user reviews for screen info.
  • 1 Hide
    Soul_keeper , August 11, 2011 1:44 PM
    "But then there are the folks who simply prefer a single workspace and ultra-high resolutions."
    ^^ me
  • 1 Hide
    lbwmoo , August 11, 2011 2:33 PM
    I too would like a better explanation on the issue of pixel density. In 2002 you could order a laptop from dell with a 15" UXGA screen with 1600x1200 resolution. It was a gorgeous screen then, and doesn't look bad now. Standalone desktop monitors, however, with that resolution start at 20" minimum. You can get 1920x1080 at screen sizes starting around 21.5" and ranging to 27" that I've seen in stores. Are there benefits to packing the same resolution into the smaller package, such as smaller pixels leading to crisper image? Is there a "sweet spot" to this resolution that balances pixel size and density vs overall space?

    It seems that 1920x1080 is the new norm, which is annoying because I don't see why I should have to give up vertical resolution just to fit the standard of the current high definition videos. 16x9 vs. 16x10 is a debate right now for me. I would rather have 16x10 because more screen real estate is better, but it seems that the 16x10 front has stagnated. All the new goodies are going into 16x9, with the exception of the 30" 2560x1600 models.
  • 0 Hide
    pirateboy , August 11, 2011 3:21 PM
    jacobdrj30" Dell IPS, Apple Cinima Display, IMac 27/30" display, TV's for use as TV monitors. 3d Monitors. Quad LCD monitors (RGB+Yellow)... Projectors, including lag time...CNet used to do stuff like this, so did PC Mag. They stopped. Bothers me. I have to rely totally on Amazon/Newegg/TigerDirect user reviews for screen info.


    here is an excellent screen review site
    http://www.prad.de/en/monitore/index2.html
  • -1 Hide
    ram1009 , August 11, 2011 3:38 PM
    These hi res monitors are just another case of diminishing returns. You spend several times the dollars as you would on equivilent standard res monitors for a fractional improvement in performance. These are definitely not main stream items. The last time I looked Newegg only offered one monitor in this res range.
  • 1 Hide
    tmax , August 11, 2011 4:26 PM
    Nice monitors but way too much money.
  • 0 Hide
    compton , August 11, 2011 5:35 PM
    Thanks for your excellent review, Andrew. I'd like to see a 24" roundup of IPS/e-IPS. Dell has their new 2412 16:10 24" e-IPS paneled Ultrasharp out, but it's not high gamut like the 2410 and especially the 2408 (which is S-PVA, fantastic, and not for everyone). e-IPS is marching on to higher adoption, and it would be great to see how these e-IPS displays stack up.
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