NEC PA242W Review

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NEC's PA242W is a worthy addition to the line of high-end displays that NEC has become known for, offering all the features necessary for dependable, wide-gamut, color-critical work.

The "24" in the name is for the 24 inch (diagonal) size of the display, and the second "2" represents that this a brand new upgrade to the PA241 which was reviewed previously. The PA242W uses LED as the source of backlighting in the display. The LED lighting technology that has been creeping into our flashlights and light bulbs lately is also providing advantages to displays like this. Besides being longer-lasting and using less power than cold cathode fluorescent tubes, LED's are capable of a purer representation of white, without the "spikes" in the green spectrum that fluorescents are known for. LED's put out more heat than other light sources, but NEC seems to have solved this issue and has produced a great display that improves upon its predecessor.

PA242W by NEC

Links:

NEC website: http://www.necdisplay.com/p/desktop-monitors/pa242w-bk-sv

CHROMiX: https://www2.chromix.com/ColorGear/shop/manufacturerdetail.cxsa?contribid=12495

The following tests were run at D65, 120 cd/m2 and L* gamma, using the NEC branded "SpectraSensor Pro", unless otherwise noted.

Contents

Color gamut

Gamut comparison between PA242W and AdobeRGB

A wide color gamut is one of the main reasons to invest in high end, color critical display like this. You want to be able to view as many colors as possible, so that you can see all the colors in your original image and preview what it will look like when printed out on various output sources. The advertising claims 99 % of Adobe1998 and my rough visual estimate would confirm that. There is plenty of color in the reds, magentas and some cyans that goes far beyond the Adobe gamut, but just a few places where super saturated yellow-greens in AdobeRGB are not found in the NEC242 gamut. It is certainly close enough to be very effective for viewing these colors. Photographers using AdobeRGB as their working space will be in great shape, and those using ProPhoto will get to see the added reds on this display.

(WHITE) = AdobeRGB

SpectraSensor Pro

A wide gamut monitor like this requires specific measurement devices capable of accurately measuring the saturated colors involved. (We don't recommend a DTP-94 device or an i1Display2 for these displays for example.) Ideally, the NEC's version of X-Rite's i1Display Pro - called here the SpectraSensor Pro - should be used. In our tests, the X-Rite version of this instrument will work equally well, and the use of a spectrophotometer, such as an i1Pro will work well too.


We have created several profiles using the NEC SpectraView software and using the various measurement devices it supports:

Gamut volumes are calculated using ColorThink Pro. Gamut volumes vary slightly depending on the instrument used, but these are all very close. Note that these gamut volumes are about 6% higher that those of the PA241W we tested. This confirms that you're getting more color with this display!

 Gamut volume with monitor profiling instruments
NEC SpectraSensor Pro device>1,371,000
X-Rite i1Display Pro colorimeter>1,335,000
i1Pro2 spectrophotometer>1,374,000


Calibration software

SpectraView II

main page of SpectraView II software

All high end display manufacturers offer their own software to calibrate their internal graphics processors, and SpectraView II is the NEC software that is made specifically for calibrating NEC displays. It requires use of any modern colorimeter or spectrophotometer, and the best results are obtained through use of their self-branded NEC SpectraSensor Pro colorimeter. This combination seems to work very well, creating profiles that are virtually identical to those made using an i1Pro2 spectrophotometer, or even the X-Rite i1Display Pro. Profiles made using older colorimeters such as an i1 Display 2 or a DTP-94 will yield different results, and are not trusted for saturated color accuracy. We would recommend using either the NEC-branded colorimeter, the X-Rite i1Display Pro (which is the same instrument), or a spectrophotometer such as an i1Pro, i1Pro2 or the ColorMunki.

As of the writing of this article, this PA242W is so new that the software supporting it was not available online at the NEC website. Included in the shipping container was version 1.1.15 of SpectraView II, which is required for support of this display.

All the options you would want are there in the SpectraView II software, including:

SpectraView only creates matrix based profiles (not look up table based profiles), and the software cannot be used to calibrate non-NEC displays, so you will need some other profiling package to calibrate your other monitors.

MultiProfiler

Alternatively, you can use an NEC program called MultiProfiler to calibrate and profile the display without the use of a measurement device. As of this article, the latest version of MultiProfiler was not supporting this display so I was not able to test it. We have reviewed MultiProfiler in the past.

Other software

Because the NEC software does not calibrate non-NEC displays, those with secondary displays attached to their computers might be interested in other calibration software. Some find it easier to calibrate using one piece of software that will calibrate all their displays.

basICColor Display

The basICcolor company in Germany actually makes the software that NEC uses, so it is no surprise that their own "Display" software will talk to the PA series of displays and create a good profile. It will recognize the NEC-branded SpectraSensor Pro.

i1Profiler by X-Rite

X-Rite's i1Profiler is also known to support writing corrections to these high end monitors. In the software, this is called using the "DDC". It does make a profile that appears to be good, but more research would need to be done to confirm this. Note that i1Profiler requires the use of an X-Rite-branded i1Display Pro. i1Profiler would not recognize the NEC SpectraSensor Pro version of the same device.

Uniformity

Click to see large version
Click to see large version

For critcal color work, it's essential that the colors you're viewing look the same regardless of where they are on the screen.

SpectraView II has its own uniformity test, where you place your sensor in 9 location on the screen while it measures the white point and compares the result. I don't find the results very useful as it only reports on the Kelvin color temperature measured & luminance - but does not report in delta E values. So the uniformity report below is based on our own tests using 99 colors and showing the delta E differences between the sections of the screen.

The uniformity across the screen was good. The average delta E difference between various locations on the screen was around 1.0, which means that on average, the difference in color between one place on the screen and another place is only just barely visible with the human eye. The worse uniformity issue was from the upper left corner to the upper right corner, and had a uniformity variation of 3.08 (dE 76). A followup test showed the uniformity off by 3.89 from upper left to upper right. I tested a set of about 100 color patches spread around the gamut . The darker patches were the worst for uniformity, which is to be expected. The nice thing about this is that you really can't tell if a black is slightly off color or not - it's the whites and light grays that show a uniformity problem easily. These values are considered hardly noticeable by most people. If that's the worst it gets, then that's still considered to be very uniform across the screen.

The NEC uniformity is corrected for at the factory using a technology they call ColorComp, and Digital Uniformity Correction. While uniformity is excellent when new, this leaves open the question of how well the uniformity holds up over time. (NEC has a four-year warranty.) If you have occasion to run this display very bright, the software will warn you if it needs to reduce uniformity in order to hit the high luminance you are aiming for. (This does not happen unless you are try to run at something like 230 cd/m2.)

Evenness

Numbers don't tell everything, so we make a visual check of the display using grays and whites on a full screen. Visually this display looks very uniform.

Black level

Much importance is place on an LCD monitor's ability to reproduce blacks and near blacks well. Blocking a backlight with liquid crystals is quite effective, but it's not as good as not having that light blasting away to begin with. Contrast ratios advertised with various displays are dependent on not only how bright a monitor can be, but also how dark. Different measurement devices have different capabilities in their abilities to measure black. This is another reason to stick with one of the measurement devices we are recommending with this display. Some flavor of the i1Display Pro or the NEC SpectraSensor Pro will measure the black on your display more accurately and give you better shadow reproduction. When looking at black measurement numbers, the lower the number, the darker is the measurement and the richer (or better) your blacks will be.

Using the NEC SpectraSensor Pro device calibrated to 236 cd/m2 (max brightness), we measured .35 cd/m2 max black.

Calibrating to a more reasonable: 120 cd/m2 brightness, we measured .14 cd/m2 black level.

This is a very, very good value for black level. By comparison, the typical off-the-shelf LCD display runs around .30 at 120 brightness.

Brightness

At maximum brightness the display was able to hit 236 cd/m2. We also calibrated and ran it at down at 60 cd/m2 without seeing any problems with shadow detail, banding, etc.

Other manufacturers have a warning against running the display at high brightness levels, but there was nothing I could find in NEC literature about that. NEC does offer some warnings against leaving a motionless image on the screen for a long time (which contributes to temporary image latency).

Banding / grayscale

Even at low luminance levels (60 cd/m2), I could not detect any colored banding on a gray scale gradient. The gray looks very neutral. I could detect a very small amount of neutral banding from about 25 - 30 %.

The software will warn you if you are moving your luminance level so low that your contrast ratio will be diminished. (This typically does not happen unless you are running down to less than 50 cd/m2, which is pretty dark!)

Highlights / Shadows

I am able to easily distinguish highlights and shadows of 1 L value difference in Photoshop.

Angle of view

The specs report an viewing angle of 178o which seems to be about right. There is no problem viewing image uniformly from one side of the display to the other. If viewing extremely off-axis, we will see changes in color and brightness as is expected. Up-and-down variation is a bit more pronounced than the side-by-side variation.

Rotation and monitor stand

The display rotates on the stand between vertical and horizontal. There is no "automatic" image rotation - although the OSD rotates with the screen automatically.

The display and the stand together are not quite as heavy as the larger units like the PA271 for example. The 242 with the stand is about 24 pounds, and there is a "handle" built into the top of the back of the monitor to allow for easier lifting and moving.

The stand allows movement from as far down as almost sitting on the table top - to about 6 inches high. It can swivel left and right and has a total movement of almost 90 degrees, although it might take an extra push to get it going at first. The face of the display can be positioned from about -5 degrees (more than fully upright), to laid back at about 20 degrees.

More items of secondary importance to photographers

USB Hub

There is a switchable, built-in USB hub which essentially allows you to control two computers with only one keyboard and mouse. Several displays out there allow you to switch between video input signals, but if you run your USB keyboard and mouse cables into and out of this built-in USB hub, you can use the switches on the front of the display to quickly switch between two computers, and continue using just one set of keyboard and mouse for both.

Size

The PA242 is a 24-inch diagonal screen which measures out to about 20.4 inches wide by 12.75 high. This is more than enough to fit the images of two 8.5 x 11 sheets side-by-side.

VIDEO CONNECTIONS

There are 4 different video protocol connection types on the PA242W:

VGA (analog) is provided to be able to handle older legacy connections or a 2nd monitor, but it is not recommended for serious color work. A digital connection (DisplayPort or DVI) allows you to benefit from the unit's internal graphics. DVI-D has been the standard for a few years now and gives great performance at 8-bit depth for each channel out a palette of 16.7 million RGB combinations. DisplayPort on the other hand provides up to 10-bits per channel out of a palette of 1.07 billion RGB combinations. Believe it or not, we found no difference with 'color management-level' accuracy between these two viewing environments. Granted, more color 'depth' is visually evident when viewing with 10-bit resolution via DisplayPort (versus DVI), but for those users whose highest priority is color accuracy, both connection types allow comparable calibration and profiling results. More visual information doesn't equate to more sampling information for the emissive measurements.

A compatible display (such as an NEC PA-series display) and DisplayPort connections are just two of the components necessary in order to view true 10-bit color depth on your computer system. For this to work, every component in the chain requires 10-bit support. So you also need your application (ie: Photoshop), operating system, video card, and video card driver to support 10-bit color as well.

One of the last hurdles has been finding a PCI v2 DisplayPort compatible video card that works with your system and is affordable. There are several mainstream cards from ATI, nVidia and Matrox that work well, but are pretty expensive right now as this is a newer technology. Currently only the very high end cards offer 10-bit DisplayPort support even though there are many that offer DisplayPort connections.

MultiSync Soundbar Pro

This display does not come with speakers. If you really need sound connected to your display, NEC offers the MultiSync Soundbar which attaches to the bottom of the display. It takes a couple of screws, a mini usb cable for power, and a 1/8 inch audio cable. Acoustically, this is nothing to write home about, but the sound bar makes a smart addition visually.

Hood

NEC does offer a hood for a 24 inch display (NEC hood part# HDPA212426) which can be purchased separately:
http://www2.chromix.com/colorgear/shop/productdetail.cxsa?toolid=50128&pid=10449

or, see the CHROMiX Blog for ideas on making a monitor hood:
http://blog.chromix.com/2010/05/monitor-hoods-for-everyone.html

Official Specs


Links and other information:

NEC website: http://www.necdisplay.com/p/desktop-monitors/pa242w-bk-sv

CHROMiX: https://www2.chromix.com/ColorGear/shop/manufacturerdetail.cxsa?contribid=12495



August 13, 2013


Patrick Herold

CHROMiX Technician
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