It was back in April that we took a look at NEC's new 24" Professional screen, the PA241W. We knew at the time that NEC also had a couple of other models up their sleeve as well, namely a 27" PA271W and a 30" PA301W. We now have the newly released 27" model with us for testing and we're keen to see if it can match some of the excellent high end performance we saw from its smaller counterpart. Like the other PA series monitors, the PA271W is of course primarily aimed at the professional market, being aimed at colour enthusiasts and graphics designers primarily. We will of course run all our usual tests on the monitor to put it through its paces, while also trying to expand a little in some of the key areas. Admittedly this is a very high end screen and if you are looking for even more detail then I would advise you to also read some further reviews where they may explore the colour capabilities and profiling in much more detail.

The PA271W is really quite similar to the 24" model, just on a larger scale. The extra screen size does offer a boosted resolution of 2560 x 1440 which is a major difference compared with the 1920 x 1200 of the PA241W. Apart from that, the rest of the spec remains pretty similar as you will see below. Feature wise, the PA271W sports a Performance-IPS (p-IPS) panel promising some excellent all round performance we have come to expect from this technology. It's "10-bit" (8-bit + AFRC) panel is combined with a 14-bit 3D Look Up Table (LUT) and extended colour space, along with further technologies to improve uniformity and viewing conditions. We will look at these in more detail later on, but for now, here is the spec:
 

Above: Front and back views of the PA271W

Like the 24" model, the NEC PA241W design is quite chunky from a side view, with the actual panel area being about 8.5cm thick. The stand and screen are quite big but very sturdy and well built and overall the screen is heavy (30 lbs. / 13.6 kg). There's a carry handle situated at the top on the back to make life a bit easier, but this is not one you'd want to move around much. The bezel around the screen is small and thin (20mm) and gives the screen an attractive and sleek feel. The base of the stand is sturdy and balanced and although simple in design, looks pretty nice on the desk in my opinion. The panel features a normal Anti-glare (AG) coating as opposed to any glossy solution. It is a fairly grainy coating as is common for IPS panels and so some people might be bothered by the grainy or 'dirty' look, particularly on white. However, this AG coating is the popular choice for professional grade screens and is nothing new.

Above: Rear views of the screen

Above: Rotated portrait views of the screen.

 

The screen offers a very good range or ergonomic adjustments. There's a decent 150mm height adjustment available which is pretty smooth and easy to position. It is a little heavy due to the size of the screen however so is not as easy as it was on the PA241W. The tilt range  is also very good, being easy to tilt backwards with a smooth movement. Tilting it  forward is quite stiff however. The pivot function is too stiff, and due to the weight of the screen you really end up moving the whole base as opposed to pivoting the screen with the stand remaining stationary. The rotate feature is easy to move but may be a little unusable on a screen this size in practice. It should be very easy to obtain optimum viewing position and alignment from this screen and nice to see everything included.

Above: Front side views

Above: Interface options from the screen when rotated into portrait mode

The back of the screen features a reasonable range of interface options. There are two DVI Dual-Link connections and a DisplayPort. There is no D-sub available since it would not be able to handle the screens 2560 x 1440 resolution. There are also two USB up and two USB downstream connections. You are able to connect the screen to two different PC's if you want via the upstream connection, meaning anything connect to the monitor can potentially work with both PC's when that upstream is selected (e.g. digital camera, printer, scanner etc). You can select which upstream is active via the OSD menu. There's another USB downstream connection on the right hand edge of the screen as well for easy access. Sadly no memory card reader on this model though, which is something I find useful personally. I think given the popularity of HDMI in the market at the moment it would have also been nice to see that featured for connecting external devices.

Above: OSD operational buttons. Click for larger version

In the bottom right hand corner are the buttons for controlling the OSD menu, as shown above. There's the ambient light sensor as well (far left) which helps detect your working conditions and adjusts the brightness automatically if you have the feature enabled. The power LED glows a fairly bright blue colour but can be turned down (or up) in the advanced OSD menu, or even changed to green. In standby it glows orange. The OSD menu buttons give quick access to interface input (input button), brightness (left and right), the picture preset modes (up and down) and Picture In Picture on/off selection (PiP button).

 

The OSD menu is pretty thorough and easy to navigate and the same as we saw with the PA241W as you'd expect. Pressing the 'menu' button on the controls brings up some guidelines in the bottom right hand corner of the screen as well, telling you what each of the buttons will do in the given menu section. The image above shows the colour preset mode screen where you can select between a series of presets including sRGB and Adobe RGB emulation modes. More on those later. You can also control colour temperature (white point) and six axis adjustment of colour channels.

The colour settings menu also gives you access to the 'advanced menu' which looks like the above. Once you've entered into here you have even more control over settings, and there is now access to advanced features relating to panel uniformity (ColorComp) and response time (Response Improve) which we will look at later.

The menu also gives access to the Picture In Picture and Picture By Picture modes available. There's plenty of options here for displaying multiple inputs at once, and the configuration is also shown above.

One last section I wanted to mention now was the 'AmbiBright' auto-brightness feature. You can select this in the advanced menu and it enables the ambient light sensor built into the screen. This automatically adjusts your backlight (brightness) setting depending on your working conditions. Transitions were pretty smooth and effective and this is a nice feature in my opinion. I like to see this from modern screens, very handy for office work and changing lighting conditions in your room.

After prolonged use, the top of the screen becomes pretty warm and you do feel that the screen is giving off a reasonable amount of heat in your room. There was a very slight 'electronic buzz' if you listen from up very close. Nothing you would notice in normal conditions though I don't think.

We tested the screen at factory settings and once calibrated (see calibration section). At default settings, and without external USB devices connected, the screen used 93.9W of power. After calibration, when the screens brightness control was adjusted down to 165 (High Bright preset mode to achieve 120 cd/m² luminance), the power consumption was 81.7W. There are also two 'ECO mode' presets available via the OSD should you want to try and reduce the power consumption even more. I expect maybe these are useful within an office environment. Mode 1 decreases the brightness range in the OSD up to 200 cd/m² maximum. Since we had calibrated the High Bright preset mode to 165 cd/m² already, this didn't impact our power consumption. Mode 2 descreases the brightness range up to 100 cd/m², and so when you change to this mode it automatically adjusts your brightness setting down to 100 if you are set above like we were. This did reduce power consumption to 63.3W. In standby the screen uses only 1.9W which is good.

 

Colour Accuracy, Black Depth and Contrast

• 10-bit Panel - The NEC PA271W utilises a 10-bit (8-bit + AFRC) 'performance IPS' (p-IPS) panel. This is a name given by NEC to the high end 10-bit IPS panels being used in their PA series of screens, but technically the panel remains the same as the so called H-IPS panels in terms of pixel structure. It's still an H-IPS panel produced by LG.Display (the same LM270WQ2 module as used in the Dell U2711 in fact), but NEC have chosen to refer to it as a 'performance IPS' panel, hence the p-IPS. Technically this is an 8-bit panel with Frame Rate Control on the panel side to boost the colour depth to 1.07 billion colours. 10-bit support does require an end to end "10-bit journey" however so it is not always possible to put this into practice. Have a read of this article which discusses it in more detail.
  
  It's all very well saying a panel is capable of 10-bit colour depth (1.07 billion colour palette) as opposed to an 8-bit colour depth (16.7 million colours), but you need to take into account whether this is practically useable and whether you're ever going to truly use that colour depth. Apart from the requirements of your application, operating system, graphics card and software, one more pertinent limitation is from a display point of view, where there must be an interface which can support 10-bit colour depth. Thankfully the PA271W does include a DisplayPort interface capable of handling a 10-bit colour depth. If you use the DVI interface you can only take advantage of 16.7 million colours.
  
   

• 14-bit 3D LUT - Regardless of whether you have a true 10-bit colour depth being displayed, a screen with 10-bit capabilities still has its advantages. The monitor should still be capable of scaling the colours well, even from 24-bit sources. Most of these 10-bit panels will also be coupled with extended internal processing which will help improve accuracy and these are better translated onto a 10-bit panel than they would be onto an 8-bit panel, giving less deviation and less chance of banding issues. Simple LCD monitors work with internal signal processing with 8-bit accuracy (256 steps per primary colour). Depending on the desired white point the intensity of one or more channels must be reduced considerably. This can result in a considerable loss in the amount of steps in the colours that have been reduced and this in a loss of display quality. The result is posterization. Highlights and shadows can also be affected.
  
  The PA271W offers a programmable 14-bit 3D LUT to help offer smooth gradients and provide clarity in subtle detail. As well as being 14-bits per channel, the LUT is described here as being 3D. Whereas a typical 1D LUT adjusts colour on separate tables for each red, green, and blue, a 3D LUT accomplishes this on a single, mixed-colour cubic table. A 3D LUT improves the monitor's additive colour mixture (combination of RGB), a key factor in its ability to display neutral grey tones. This 14-bit LUT means that you have a palette of 4.3 trillion colours when using 10-bit panel capability (DisplayPort), or 65 billion when using DVI.
   

• Colour Gamut - Like many modern displays, the screen uses enhanced W-CCFL backlighting and can offer a colour gamut covering 102% of the NTSC colour space. This also covers 97.1% of the Adobe RGB and 100% of the sRGB gamut. The screen offers sRGB and Adobe RGB emulation modes as well which we will look at shortly.

 

An important thing to consider for most users is how a screen will perform out of the box and with some basic manual adjustments. Since most users won't have access to hardware colorimeter tools, it is important to understand how the screen is going to perform in terms of colour accuracy for the average user. I restored my graphics card to default settings and set it to its standard profile. The PA271W was tested at default factory settings using the DL-DVI interface, and analysed using LaCie's Blue Eye Pro colorimeter and their accompanying software suite.

It should be noted that I manually disabled the ColorComp uniformity adjustment and Metamerism setting for these tests. All other settings were left at default

Default settings of the screen were as follows:

NEC PA2471W - Default Factory Settings

Default settings of the screen were tested first of all. The display was in the 'High Bright' preset mode at this point which is the  factory default and has the highest brightness settings. The actual monitor brightness control is set at 220 cd/m² out of the box, but does range up to 400 cd/m² if needed. The screen did feel very bright to the naked eye but  colours felt bright, vivid and even.

Results from our testing of the PA271W at default factory settings were very good. Most areas performed very well which was pleasing. The CIE diagram on the left hand side shows the colour space which the monitor can produce as compared with the sRGB reference space. As you can see, the monitor stretches beyond the sRGB space in greens and reds particularly, and the triangle confirms the backlighting does offer a wide colour gamut as advertised. Wide colour gamuts are not for everyone though, and I would thoroughly recommend a read of this article over at X-bit Labs, which covers the pros and cons well. At the end of the day it boils down to the content you are viewing and the colour spaces you want to work in. Given that this screen is aimed primarily at colour enthusiasts and the professional market, I'm sure they would be very aware of the pros and cons of using a wide gamut screen. A lot of colour professional work is also conducted in extended colour spaces (especially Adobe RGB) so the ability to support this is important when choosing a new monitor.

Gamma was an area which was pleasing, with default settings giving us a measurement of 2.2 average, that being the target in our tests and the default for computer monitors. Luminance was recorded at a fairly high 171 cd/m² which is a little bright for prolonged use in my opinion. The target we aim for in these tests is 120 cd/m², that being the recommended luminance for LCD screens in normal lighting conditions. The OSD setting at default was only 220, with the menu providing a range all the way up to 400 if you wanted. At this luminance, black depth was a moderate 0.29 cd/m², giving an average contrast ratio of 589:1. This was a fairly good result from an IPS matrix but we had seen significantly  better from the PA241W (865:1) and the competing Dell U2711 (832:1). Colour temperature / white point was also very good at default settings, being recorded at 6441k, only 1% deviance from our target of 6500k, the temperature of daylight.

Testing with the colorimeter revealed the graph on the right hand side above, showing DeltaE (dE 94) values across 16 shades. As a reminder, the lower these bars down the Y-axis, the better, in terms of colour accuracy. For reference, LaCie describe the DeltaE readings as:

• If DeltaE >3, the color displayed is significantly different from the theoretical one, meaning that the difference will be perceptible to the viewer.

• If DeltaE <2, LaCie considers the calibration a success; there remains a slight difference, but it is barely undetectable.

• If DeltaE < 1, the color fidelity is excellent.

 

The default settings gave us a very good result which is excellent to see. This is a professional grade screen so perhaps it is not suprising given the price. Average dE was 1.1 giving a very slight difference between requested and displayed colours. This only ranged up to 2.6 in the worst case so again a very good result. You should be able to get even better accuracy out of this screen with calibration and profiling of course. Apart from the brightness of the screen, the PA271W met our targets very well even at default settings.
 

Although we tested the default mode here where the preset was left on 'high bright', there are also preset modes for Adobe RGB, sRGB, 'Full' (giving native display colour gamut), and DCI (Digital Camera). There are also 3 programmable preset modes designed for �MultiProfiler� software or hardware calibration settings. We will test some of these below.

 

NEC PA271W - Default 'Full' Preset Mode

 

NEC PA271W - Default Adobe RGB Mode

Again everything else was left at default, but I switched to the Adobe RGB preset mode. The brightness setting remained at 160 in the OSD and white point was set at 6500k as with the 'full' preset mode.

The colour space was reduced slightly from the monitors native gamut, with the Adobe RGB mode emulating the Adobe RGB colour space as best it could. The spec states that the screen can cover 97.1% of the Adobe RGB space. If you compare the monitors gamut in the CIE diagram to that from the default settings you will see the triangle is reduced a little in reds, greens and blues. This brings it closer to the Adobe RGB reference, but it was not quite perfect. The gamut extended a little beyond the reference in reds and didn't quite cover all the green shades it was supposed to. This must be where the missing 2.9% comes from.

Some other competing models in this size range like the Dell U2410 offer factory calibrated presets for Adobe RGB and sRGB, which did help provide some improved colour accuracy out of the box. The Dell had a well calibrated gamma of 2.2 and dE average was down to 2.9 thanks to the factory calibration. The NEC PA271W offered equally impressive performance out of the box in Adobe RGB mode. Gamma was 2.2, being only 1% out from our target. Colour temperature was a little off at 5844k (10% deviation) but luminance was more comfortable than the 'high bright' mode at 124 cd/m². Black depth was now 0.21 giving us a static contrast ratio of 589:1. This matched the 'high bright' preset and was a little better than the 'full' mode which seemed to take a hit in regards to contrast. Colour accuracy was also quite good overall with dE average of 2.5. However, this ranged up to 6.7 maximum and was not as good as the 'high bright' or 'full' preset modes.

 

NEC PA271W - Default sRGB Mode

Again everything else was left at default, but I switched to the sRGB preset mode. The brightness setting automatically adjusted to 80 in the OSD and white point was set at 6500k. There was a significant drop in the screens luminance as a result.

Like the Adobe RGB mode, this preset emulates a smaller colour space, this time the sRGB reference. Colour space was reduced significantly and was fairly close to the sRGB standard. It didn't quite cover all the green shades and was a little too wide in reds. Luminance dropped quite noticeably when switching to this mode, and the colorimeter recorded luminance as 63 cd/m² now. Black depth was reduced down to 0.12 cd/m² giving us a contrast ratio of 528:1. Colour temperature was no closer to the target, being 11% out from 6500k. The default 'High Bright' mode was closest to the target white point out of the box set at 'Native' as opposed to 6500k in the OSD. dE average was now 3.3 with a maximum of 9.8. Colour accuracy was not as good as in the other modes, probably due to the emulation of a smaller colour space at a hardware level.

 

Calibration Results

 

 

 

I wanted to calibrate the screen in each of the main preset modes to determine what was possible with optimum settings and profiling. I use the LaCie Blue Eye Pro colorimeter and software package to achieve these results and reports. One thing to note was that I had to enter the advanced OSD menu and disable the 'uniformity' and metamerism features for these tests.

 

Please remember that these are all software based graphics card profiling "calibrations" as opposed to hardware level true calibration which we will come onto shortly. These are the normal calibration methods we use for our monitor reviews which creates a profile which is activated at a software level in the graphics card. This is more than adequate for most users and is all you really need for nearly all the mainstream monitors anyway. In fact, most don't even have the option for hardware level calibration, so you have to make do with software profiling only. For professional use and high end colour work these kind of profiles, although good, are not acceptable. You need full hardware calibration which can make adjustments at a hardware level and to the monitors extended LUT. This is what the high end professional market need and want from a screen. The PA271W offers the hardware capabilities to do this form of calibration as well, which we will come onto shortly.

 

NEC PA271W - Software Calibrated Settings - Preset Mode 'High Bright'

Monitor OSD Option	Adjusted Setting
Brightness	165
Contrast	---
Preset Mode	High Bright (3)
White Mode	Native

	Calibrated Settings, 'High Bright' Mode
luminance (cd/m2)	120
Black Point (cd/m2)	0.20
Contrast Ratio	600:1

 

I left the screen in its default 'High Bright' mode first of all to see what proper software level calibration could achieve. White mode (colour temperature) was left in 'Native' mode since this had returned our most accurate reading out of the box in terms of reaching our target of 6500k.

 

Calibration was a great success. Gamma had already been accurate at default factory settings but remained at 2.2 after calibration as one would hope. Colour temperature was very good at 6539k (1% out) although this was already good out of the box in the native mode. Luminance was now a perfect 120 cd/m² with OSD brightness set at 165. This gave us an average black depth of 0.20 and contrast ratio of 600:1. Best of all, colour accuracy was now excellent, with average dE at 0.2 and maximum only at 0.8. This was improved from the default of 1.1 average / 2.6 maximum in this preset mode. LaCie would consider colour fidelity to be excellent across the whole range. This was a very good result and exactly what you would expect and hope for from a high end screen such as this. You can use our settings and calibrated ICC profile on your PA271W as well if you want. See our ICC profile database for more information.

 

NEC PA271W - Software Calibrated Settings - Preset Mode 'Full'

Monitor OSD Option	Adjusted Setting
Brightness	165
Contrast	---
Preset Mode	Full (4)
White Mode	6500k

	Calibrated Settings, 'Full' Preset Mode
luminance (cd/m2)	119
Black Point (cd/m2)	0.22
Contrast Ratio	541:1

 

I changed back to the 'Full' preset mode and software calibrated the screen again. Again, this produced pleasing results in most regards. Gamma was spot on at 2.2 average. Colour temperature was now 6532k, being only <0.5% out from the target of 6500k. This corrected the 8% deviation we saw in colour temperature at default settings in this preset. With a luminance at 119 cd/m² as hoped, black depth was 0.22 cd/m² however, giving a slightly lower static contrast ratio than we had reached in the 'High Bright' mode of 541:1. This was a similar pattern to what we saw in the default high bright vs. full modes. The Full mode seems to take a slight hit in terms of black depth and contrast. Colour accuracy was again corrected very nicely, with dE average of 0.2 (down from 1.7 default) and a maximum of only 0.7 (down from 4.0). The colour accuracy matched the calibrated 'High Bright' preset,  and so both were very good in this regard. I'd recommend using the 'High bright' mode to achieve the best results from a graphics card LUT correction perspective as it offers a slightly better contrast. Again, ICC profile available if you want it in our ICC profile database.

 

NEC PA271W - Software Calibrated Settings - Preset Mode 'Adobe RGB'

Monitor OSD Option	Adjusted Setting
Brightness	170
Contrast	---
Preset Mode	Adobe RGB (1)
White Mode	6500k

	Calibrated Settings, 'Adobe RGB' Mode
luminance (cd/m2)	119.5
Black Point (cd/m2)	0.22
Contrast Ratio	543:1

 

Software calibration in the Adobe RGB preset mode was a good change from default settings on the most part. Colour temperature was less than 0.5% deviation now at 6505k, and gamma was spot on at 2.2. Colour accuracy was significantly improved, with dE average now 0.5 (down from 2.5 at default). dE maximum was also only 1.1 (down from 6.7) which was again a good result. Like the 'full' preset mode, contrast ratio was around 540:1 and a little behind the 600:1 of the 'high bright' mode. Apart from that this shows calibration in the Adobe RGB preset can produce some very good results if you want to work in this simulated colour space more closely. Again, ICC profile available if you want it in our ICC profile database.

 

NEC PA271W - Software Calibrated Settings - Preset Mode 'sRGB'

 

I software calibrated the screen in the sRGB preset mode as well. The gamma, colour temperature and luminance targets were met well. Colour accuracy was again improved nicely, with dE average dropping from default of 3.3 down to 0.3. Maximum dE dropped from 9.8 to 0.9. Pleasing to see that the sRGB emulation mode helped reduce the colour space close to the reference gamut, and also allowed for some decent colour accuracy once calibrated. Again the limitation with this mode is the slightly lower contrast ratio of 523:1 compared with the 'high bright' preset. Again, ICC profile available if you want it in our ICC profile database.

 

You may note that the colour space being produced here is not quite 100% accurate to the sRGB reference triangle. I had a long conversation with NEC about this as well. They clarified that the sRGB mode is a fairly simple preset, designed to closely simulate the sRGB colour space. The result is very similar to other sRGB simulation modes we have seen from other screens so this is not uncommon. It covers the space pretty well, certainly restricting the gamut compared with the default. However, it doesn't quite cover all the green shades and extends a little past the red shades required. This is more than adequate for most users anyway and this basic simulation mode is there to offer that reduced gamut if you want it.

 

NEC also informed me that sometime next year there will be an update to the SpectraView Profiler European software (see below) which allows you to first of all calibrate the screen as normal, but will provide further options to then cut back the colour space to more accurately match the sRGB reference if you need it. Carrying out these alterations using the Profiler software and a SV version of the screen (again see next sections) will produce the most accurate results.

 

 

 

I tested the screen using various colour gradients in all of these preset modes which showed smooth transitions and no apparent banding. There was some noticeable gradation in darker tones which I would expect are eliminated if you can take advantage of the 10-bit panel depth (8-bit +AFRC). Unfortunately I do not have the means to fully test the 10-bit capability of the p-IPS panel.

 

 

 

SpectraView Profiler European Software

 

To take full advantage of the screen for calibration and profiling, NEC have built in a hardware calibration feature which allows you to make corrections to the monitors 14-bit 3D LUT. This can provide even better colour accuracy and allows you to store your calibration in the screens hardware. Professional markets and those working with colour critical content require this kind of high end hardware calibration so this is one of the reasons this screen separates itself from the more mainstream models. NEC have their own specific software for this hardware calibration which is called SpectraView. There are actually two versions of this software, both offering different capabilities in terms of the calibration possible and both designed for different international markets.

 

 

 

In Europe the "SpectraView Profiler" software is provided by BasICColor who offer a free 14 day license for the full version of the software. After speaking with NEC Europe to clarify we discovered that this software allows three levels of calibration of the PA series, depending on whether you have bought the regular PA monitor or the special SpectraView II edition in European countries. The latter is referred to over here as the NEC PA271W-SV or the SpectraView Reference 271. It comes at a higher cost but is aimed at users who require that extra level of specialist performance and high end professional application. I would like to emphasise that there are significant differences between the regular PA271W and the SV edition of the screen, something which every NEC representative highlighted to me during our conversations.

 

The SV model in Europe was produced in addition to the regular PA model because of the high demands of the European market and the expectations they have when it comes to high end professional screens. NEC therefore offer the SV version which include panels which have been hand picked and selected to be the absolute top end in terms of dE performance, gamma correction etc. These are then tuned and altered to enhance the performance even further, with advanced adjustments being made in the factory to ensure these are the absolute cream of the crop. The SV model is then packaged with a calibration hood, SpectraView Profiler software and license and a factory report validating the performance of the panel selected and confirming the tuning completed. It is not packaged with a hardware colorimeter in Europe so you would need to already own one or plan to purchase one for proper calibration. The SV models do come with a 6 month pixel defect guarantee as well. The normal PA version does not go through this extra process and does not come with the additional extras.

 

Also, importantly for calibration the PA271W regular edition and PA271W-SV have a firmware difference which allows for different levels of calibration. The PA271W only allows you to use the European software to calibrate at a software (graphics card LUT) level alone, or at a hard/software level which also controls limited monitor settings such as brightness and the RGB channels automatically. It does not however control the monitors 14-bit LUT and the option for "hardware calibration" within the software is greyed out. If you purchase the SV version of the screen, the firmware communicates with the software automatically and the software will then allow full calibration of the monitor's LUT.

 

 

I installed the latest version of the SpectraView Profiler European software which was v4.1.22 and I'll give you a quick tour as well as some calibration results. When you load up the software you are presented with various options which you can configure before carrying out a calibration of your screen. The information section confirms your current active profile (here just showing one I had just made with the SV software) along with your defined calibration targets. You will see here that we are aiming for 6500k white point, 2.2 gamma and 120 cd/m² luminance. Settings can be defined in the menu on the left.

 

 

 

Entering the settings menu gives you a whole range of options. I won't go through them all as they are self explanatory really. You will see that within the 'presets' section you can choose the calibration method. As I've already explained, full hardware calibration is greyed out as we are testing the regular PA271W screen, but I have selected combined hard- and software calibration. Within the luminance/contrast ratio section you can set the targets for white and black, as well as do a quick simple measure of the current settings.

 

 

Entering the 'Review' section presents you with several options you can use to validate the success of your calibration as well as test things like ambient light conditions and the effects of the viewing booth (hood).

 

 

The ambient light checking section is shown above

 

 

I disabled all active profiles and returned the screen to default settings again before calibrating with the SV European software (I left the screen in 'high bright' mode to start with but it changes you from this preset straight away). The calibration process itself takes around 3 minutes to complete with the sample window displaying the usual white, black, grey and coloured images in front of the colorimeter in order to adjust white point, luminance, grey balance etc.

 

 

 

Since I have selected the combined hard/software calibration option, the software also controls an adjustment of the screen OSD settings, and so the preset mode automatically defaults into setting '5' which is then named as "SpectraView II". The brightness and RGB settings are then not available for manual adjustment in the OSD as the software has controlled these while profiling.

 

At the end of this process you are presented with a summary window as shown above. This confirms the success of your calibration against the targets. If you press the 'validate' button in the bottom right you can carry out a more detailed test and report of the calibration which takes around 30 seconds.

 

 

The validation process presents you with a summary report like the above. As you can see, this report now includes details dE information relating to colour accuracy. Average dE was recorded at 0.28, with maximum of only 0.64. Colour fidelity would be considered excellent all round, and the calibration seemed to offer excellent results. It would be interesting to run this same BasICColor software with the SV edition of the screen to allow full LUT correction at a hardware level. I may have chance to test one in the near future so I will update the article if I do.

 

NEC PA271W - Calibrated Settings - SpectraView Profiler European

 

I ran the LaCie test and report feature on our newly calibrated profile to see what it thought of the results as well. Obviously there will be some deviation between different sets of software and it's probably arguable which is more accurate here anyway, but I include it for reference since we have used it throughout all our reviews and tests. The LaCie report confirmed the results shown from the SpectraView Profiler package. Gamma, colour temperature and luminance were all corrected nicely. We had a black depth of 0.23, giving a contrast ratio of 523:1 which was almost exactly the same as the report from the SV software. Colour accuracy was also confirmed to be very good with average dE of 0.4. Maximum was listed up to 1.2, an excellent and impressive result.

 

 

 

If you return into the software you can edit the calibration curves of your monitor if you wish from within the review menu if you need to do any tweaking.

 

 

Overall I was impressed with the SV Profiler European software package. It was easy to use and set up, had a nice range of options and produced some very pleasing results. I expect it will offer even greater results when combined with the SV edition of the screen with full hardware LUT adjustments. BasICColor make some very high quality and well regarded calibration software as well, so it's no wonder this is returning us some great results. Remember, this SpectraView Profiler software does not make hardware LUT adjustments to the regular PA model, and you have to combine it with the SV edition to take advantage of that. Given the hand picked panels, extra factory tuning and the ability to complete a full hardware LUT calibration, the SV model should return even greater results than we have seen here. Again, for many in the professional market, true and full hardware calibration is a must and so this is where the SV version fits in.

 

 

 

SpectraView II US Software and Hardware Calibration

 

The other thing I wanted to take a look at is the USA version of the SpectraView II software, available from NEC's US website. The website states "The software analyzes these measurements and sends colour adjustment commands directly to the display monitor. This means that colour adjustments are made in the monitor rather than in the video graphics adapter, resulting in full use of the number of colours available on the graphics adapter and a much brighter image with the maximum possible colour gamut. With SpectraView II, the video graphics adapter is not used at all to make any gamma or Tone Response Curve corrections to the display, so the full colour resolution and fidelity of the system is maintained."

 

I clarified this with NEC who confirmed that the software will work with the PA271W regular edition, as well as the SV model and is not limited by the communication between software and monitor firmware that the European version is. However, this US software is not recommended or supported in Europe or indeed anywhere outside of the USA. NEC Europe consider it to be a bit of a shortcut to the full potential from this monitor. On the plus side, it can be used with the regular PA271W model anywhere in the World, so you can carry out a hardware level calibration of the screen even if you have not bought the SV model. This is a plus point as you can now take advantage of the hardware calibration to a degree. However on the negative side, part of the point of the SV model was to have that extra high end performance that some users in the market require. If you use this software on the regular PA model you are missing out on the hand picked panels, extra tuning and extra performance of the SV screen. This US software is also inferior (in the view of NEC Europe) to the BasICColor provided SpectraView Profiler software and does not offer the accuracy or performance that the Euro software can. Part of this relates to the fact that the US SpectraView II software can calibrate at a hardware level, but only a matrix based profile is used. The Euro software can create a hardware based table profile which is superior in accuracy.

 

As a summary I would say that the US software is a bit of a quick fix in some regards to using the PA screen with hardware calibration. For absolute top end performance you would ideally want to use the PA271-SV edition with the Euro software, giving you full table based profiling at a hardware level, and with a superior piece of software. The combo of Euro software and SV panels gives a significant advantage over the PA model with US software. In the US, the SV version of the screen is still available although apparently the only differences with the SV edition there are that it is bundled with the SV II software and a calibration tool. The screen itself remains unchanged and both packages can be used with the SV II software for hardware level calibration

 

At the time we reviewed the 24" PA241W the SpectraView II software was only at v1.1.03 which was not compatible with the PA series of screens anyway so we couldn't test it. Thankfully v1.1.05 is now available which is compatible with the PA series and we have used it here with the PA271W. When you load the software up it identifies the screen and you're away. When we tested the PA241W it just gave an error saying it was not compatible (v1.1.03). It should be noted that this is an NEC specific piece of software, and is not  supplied by BasICColor as the European version is.

 

 

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Features and benefits:

• High bit depth internal Look Up Tables (LUT's) - each LCD display monitor supported by SpectraView II features three internal 14, 12 or 10 bit LUT's (depending on model). These tables allow very precise adjustments to be made to the display's Tone Response Curve without reducing the number of displayable colours.
   

• Fully automated calibration - By making adjustments directly in the display hardware, optimal settings are configured without any user interaction. SpectraView II communicates with the display monitors using Display Data Channel - Command Interface (DDC/CI) which is a two-way communications link between the video graphics adapter and display monitor using the normal video signal cable. No extra cables are necessary.

 

 

The software itself is pretty easy to use. You are presented with a screen showing your defined target settings and your current calibration status and display. As you can see here, our 'Reviews' target set which we created aims for 6500k colour temperature (white point), 2.2 gamma and 120 cd/m² luminance. In this screenshot, the window confirms we have just calibrated the screen although when you first load up the application it of course tells you that you need to perform the calibration. If you enter the settings for the targets of your calibration you are able to configure all the options as above.

 

 

If you enter the preferences menu then you can select several specific options. The above screenshot for example shows that you can choose the accuracy of your calibration, based on the number of steps used to measure the monitors greyscale during calibration and creation of an ICC profile. A larger number will generally lead to a more accurate calibration but will take longer. You can choose from 8 up to 52 which is the highest quality. We have selected 52 for our calibration here. You can also specifiy whether your calibration priority is to maximise contrast ratio or produce the best grey scale tracking. We opted for best contrast ratio since the results we had obtained already were pretty average in regards to black depth and contrast ratio. We did try the process with several different options on many occasions to see what we could get out of the screen. The results below were the best we saw.

 

 

 

There is also a section in the software to control the monitor settings. In this case we can control the power LED brightness and colour (blue or green) and the ColorComp screen uniformity compensation. We left ColorComp off for the calibration here.

 

 

I restored my graphics card and screen to default settings to perform a calibration with the SpectraView II software. As you follow through the calibration process you are prompted to place your colorimeter in the centre of the screen to begin. A fairly small sample circle appears to carry out the calibration behind where you have placed the device. The rest of the screen is black and a progress indicator is shown in the top left hand corner like the one above. This shows you an overall progress as well as various steps to adjust brightness, white point etc. At a setting of 52 steps this whole process took around 5 minutes but is all automated.

 

 

As with the European software, the whole process is automated and the screen automatically enters into the "5" preset mode which is named 'SpectraView II'. The options in the brightness and RGB menus are then not available. Like the Euro software, the package makes these adjustments for you, but goes a step further to calibrate the internal hardware 14-bit LUT as well. That is only possible with the Euro software when using the SV version of the screen.

 

 

 

At the end of the process you are presented with a validation screen as shown above, with several tabs of useful information. You can see from the above that the colour temperature was calibrated to 6493k, very close to the target setting. Luminance was corrected to 119.4 c/m² giving us a black depth of 0.21cd/m² and a contrast ratio of 555:1. The ICC profile activated is also shown. I also tried this same calibration but with greyscale tracking being the priority as opposed to contrast ratio. This returned us a contrast ratio of around 478:1 instead and didn't really impact the colour accuracy performance as recorded in the sections below.

 

 

The colour gamut is also shown relative to a selected reference colour space, in this instance shown by the blue triangle of the sRGB colour space.

 

 

The gamma curves are also available showing the target and calibrated results. In this instances the lines are very accurate showing a good calibration result.

 

 

The colour tracking tab gives you a report of the greyscale deltaE achieved. On average dE was 0.58, ranging up to 1.43 maximum. A very good result. At 0% black, it seemed to have an issue with colour fidelity, perhaps related to the apparent poor black depth achievable from this panel. This is really the only area which let the calibration down.

 

The whole process using this software was very easy and again provided a decent range of options to choose from. It was good to see this package was compatible with the European PA271W regular edition and allowed you to make full adjustments to the hardware LUT, albeit using a matrix profile instead of a table profile. I tested the screen using various colour gradients which showed smooth transitions and no apparent banding. There was some noticeable gradation in darker tones which I would expect are eliminated if you can take advantage of the 10-bit panel depth (8-bit +AFRC). Unfortunately I do not have the means to fully test the 10-bit capability of the p-IPS panel.

 

 

NEC PA271W - Hardware Calibrated Settings - SpectraView II (USA)

 

 

If I revert back to the LaCie software to compare the results I am given the above report. This again shows that the calibration was a great success and matches the report from the SpectraView II software very closely. Perhaps the only thing to comment on again is the dE maximum of 2.2. It doesn't show on the report above but when viewing the detailed PDF report it shows that this is in the 0% black range. This seems to be letting the results down a little bit, but dE average is still a very low 0.4. Perhaps the software has trouble correcting at the dark end of the greyscale, or perhaps it is a limitation of this particular panel. I tried many settings and calibrations but was not able to improve this any more.

 

As already discussed, I should expect using the BasICColor produced European version of the software with a PA271W-SV would give us the most accurate results with hardware calibration, but this still returned us some very pleasing performance. Remember, these adjustments are all made at a hardware LUT level offering far more accurate real-life performance than a comparatively simple graphics card correction can achieve. However, the profile is only a matrix based profile so not as accurate as a table based profile if you use the Euro software at a hardware correction level.

 

 

Calibration Performance Comparisons

 

I thought it would be useful to summarise the results from each of these preset mode calibrations in one place. The results of the SpectraView calibrations are recorded using the LaCie reports in order to keep all of these uniform:

 

 

I tested the screen with colour gradients in each of these calibrated preset modes. The gradients were very smooth and showed no sign of banding. I was unable to test the full potential of the "10-bit" colour depth due to graphics card and software limitations but expect results will be even better if you can really put it into practice. There was some very slight gradation in darker tones in my gradient tests which is common to 8-bit displays. As a side note, there was also no issue with dithering artefacts when using the sRGB or Adobe RGB emulation modes. This is something which the 24" Dell U2410 suffered from in its initial A00 release.

 

Overall, the screen could be very well calibrated in all preset modes and using both software based and hardware based methods (or a combination of the two). The screen had been calibrated in all 4 main preset modes at a software graphics card LUT level using the LaCie Blue Eye Pro package. All the results were very good, with the high bright preset holding the slight edge in terms of colour accuracy and contrast ratio. At a contrast ratio of 600:1 it was a little better than the other modes which were around 520:1 - 540:1.

 

We also then calibrated the screen using NEC's SpectraView Profiler software from Europe (v4.1.22) which carried out corrections at a graphics card LUT level, along with some control of basic hardware controls like brightness and RGB channels. This produced similar results to the LaCie calibrations, but seemed to have a minor issue with correcting the 0% black range. The US version (v1.1.05) of the SpectraView II software allowed full correction at a hardware LUT level using a matrix profile, making use of the 14-bit 3D LUT and providing significant benefits beyond what we can really tell from these reports. It again produced similar results in the LaCie report as the software based calibration had, again struggling for some reason with the 0% black accuracy.

 

It should be noted that because the software was making adjustments to the hardware LUT, there are many more accurate and detailed corrections being made which brings benefits when you come into high end graphics and professional uses. This is the type of calibration high end users would want to conduct and is the preferred option when you have a professional grade screen like this. One other thing to note is that the profile is activated and stored in the monitor itself and so is always active, no matter what workflow you are using. You don't have to worry about whether your graphics card profile is loaded in a certain application or during games / movies for instance and the benefits of a correct calibration can be carried over between each application. For even more accurate results the European SpectraView Profiler software should be combined with the SV edition of the monitor, combining tuned and tweaked screens with table based profiling at a hardware level.

 

 

 

Above I have plotted the colour accuracy reports from the NEC PA271W (best results in 'High Bright' mode) against the results of other competing models in this range we have tested. As you can see, default colour accuracy was the best we have seen at dE 1.1. Even if you do not carry out a calibration, the screen delivers accurate colours and good gamma set up. Once calibrated properly, colour accuracy is even better. At an average dE of 0.2 it is as good as any model we have tested. Maximum dE was 0.8 which puts it ever so slightly behind the NEC 2490WUXi and NEC EA231WMi (0.5 max dE). Notice that all three of these are IPS based NEC screens!? They certainly know how to give you some excellent colour accuracy from their monitors! Again keep in mind there is more to this than just a validation of a colour profile and colour accuracy reports, which does separate this screen from the more mainstream models. This kind of area can get very complex and go into a lot more detail than we have here, but needless to say the other high end features of this screen (and the PA241W) like 3D 14-bit LUT's, hardware calibration, ColorComp etc separate it from the lower cost mainstream models you see it compared against when it comes to high end professional uses.

 

 

Calibrated black depth was average, offering some slightly inferior blacks (0.20) than the PA241W (0.17) and 2490WUXi (0.19) models which proceeded it. Compared with the other 27" models here, it was also a little behind the Dell U2711 (0.18) and the TN Film based ViewSonic VX2739WM (0.15). Obviously we're talking very different screens when we compare the PA271W and the VX2739WM! It couldn't quite match the extra-deep blacks of the e-IPS based NEC EA231WMi (0.15) or Dell U2311H (0.14), but performed fairly reasonably I think. Contrast ratio of course relates to black depth once calibrated, but at 600:1, that is fairly average for a modern IPS panel. You would have hoped for a little bit more to be honest.

 

 

Advanced Colour Options

 

I'll give brief mention to some of the more advanced options available with the PA271W for colour adjustment:

 

 

Contrast Stability

 

There's a few things I wanted to talk about here. First of all, the OSD brightness control is listed in cd/m² as opposed to a percentage, and allows you to control the range from a maximum setting of 400 cd/m² all the way down to 40 cd/m² minimum. The control from 400 down to 90 cd/m² adjusts the intensity of the W-CCFL backlighting unit, and as you adjust the setting it stops at 90 initially. The 24" PA241W had the same feature but stopped at 130 cd/m² instead. You can see from the tests above that the contrast remains pretty stable across the whole range from 400 - 90 as you would hope, being recorded at around 625:1 on average. This was a good result and as you would hope from this test. The luminance was recorded at a maximum of 290 cd/m² which is a little under the advertised maximum brightness of the screen (300 cd/m²), but very close. You probably wouldn't want to use the screen at such a high brightness though as it was very intense and harsh on the eyes. The luminance ranged down to 70 cd/m² at the lowest backlight intensity which gives you a very good range in which to adjust the screen without sacrificing contrast ratio. You will probably want to adjust the setting to about 165 in the OSD for a comfortable luminance of around 120 cd/m². Black depth also descreased from 0.47 to 0.11 cd/m² at the lowest end as these adjustments were made. These results were plotted on the graph below.

 

 

The control of the backlight intensity stops when you reach the OSD setting of 90 cd/m², and for all intents and purposes you are at a setting of 0% here. However, the PA271W (like the 24" PA241W) does allow you to reduce the luminance of the screen even further down to a setting of 40 cd/m². As you go below the 90 setting, the OSD shows the value in pink, and indicates that you are no longer making backlight adjustments, but you are making digital alterations at the controller board level. This has the effect of lowering the luminance of the screen even more, but since this is a digital white level adjustemt only, it does affect contrast of the screen. Black depth cannot go any lower since you are not able to reduce the backlight intensity any more, and so even though white level is changing with the digital alterations, black depth remains at ~0.11 cd/m². Therefore the contrast ratio drops from ~625:1 to as low as 287:1 at the lowest luminance reading.

 

Compared with most other monitors you would only normally have access to the backlight intensity control so the PA271W's performance from the 400 - 90 setting is in keeping with other models we have tested. All NEC have done is add an additional digital control should you wish to reduce luminance even further. If you don't want to use this digital adjustment, but need a lower luminance than the 70 cd/m² we achieved at 90 OSD setting, remember you can achieve lower results through calibration procedures and adjustments at a graphics card LUT level.

 

Viewing Angles

 

 
 

Above: Viewing angles shown from front and side, and  from above and below. Click for larger images

Viewing angles from the NEC PA271W were very good. Being IPS based, the panel was free from the obvious blackening you will see from below on TN Film matrices, and some of the other rather obvious colour tone and contrast shifts from that technology. It was also free from the off-centre contrast shift you see from VA matrices as you move your head away from a central point. Vertically you could see a shift in the contrast as you moved your head away from a central point, especially from above. Horizontally, you had to reach an angle of about 60� before there was any significant change in contrast detectable and I thought horizontally the screen performed very well. Good wide angles from this screen as you would hope.

The PA271W does not feature an A-TW polarizer, which is sometimes used on other H-IPS based models in this sector and has been used by NEC in the past. This is designed to improve black depth at wide angles, but is rarely used nowadays. There is a rather obvious white tint to a black image when viewing the screen from an angle, something common from modern H-IPS structured panels..

 

Panel Uniformity

Measurements of the screens luminance were taken at 35 points across the panel on a pure white background. The measurements were taken using BasICColor's calibration software package, combined with the LaCie Blue Eye Pro colorimeter. The above uniformity diagram shows the difference, as a percentage, between the luminance recorded at each point on the screen, as compared with the reference point of a calibrated 120 cd/m². This is the desired level of luminance for an LCD screen in normal lighting conditions, and  the below shows the variance in the luminance across the screen compared with this point. It is worth noting that panel uniformity can vary from one screen to another, and can depend on manufacturing lines, screen transport and other local factors. This is only a guide of the uniformity of the sample screen we have for review.

Uniformity of Luminance - ColorComp Off

The above results were recorded using the screen with the 'uniformity' mode disabled. We will look at that technology in a moment. The results of this test were very good. Luminance did drop down by around -15% in the lower left hand area of the screen, down to a minimum of 105 cd/m² in the corner area and was a little darker along the left hand edge. On the whole though 75% of the screen area was less than 5% out from the target luminance which was very impressive. I tested the screen with various coloured backgrounds and saw no colour tinting issues.
 

Uniformity Mode - ColorComp

 

   

 

The PA271W manual explains what this function does quite well: "This function electronically compensates for the slight variations in the white uniformity level as well as for deviations in colour that may occur throughout the display area of the screen. These variations are characteristic of LCD panel technology. This function improves the colour and evens out the luminance uniformity of the display. Note that using the 'Uniformity' feature does reduce the overall peak luminance of the display. If greater luminance is desired over the uniform performance of the display, then this option should be turned off. A higher number produces a better effect, but may also reduce contrast ratio."

Uniformity of Luminance - ColorComp Level 5

Uniformity mode is accessable via the advanced OSD menu as shown in the image above. I tested this feature set at level '5' to see whether it worked well or not. I had tested the feature on the PA241W as well which had returned pleasing results. The outcome was the same with the PA271W. Uniformity was improved nicely across the screen, even from our starting point without the technology turned on, which was frankly very good anyway. Luminance ranged down to 115 (bottom left hand corner) and up to 125 (top right hand corner), but overall the luminance of the whole screen was <5% out from the target. This technology did a very good job and is an excellent feature to include for those who worry about uniformity of images and colour.

Above: All black screen in a darkened room. Click for larger version

As usual we also tested the screen with an all black image and in a darkened room. A camera was used to capture the result. There was some slight uniformity differences in the top left and bottom right hand corners of the screen where there was some backlight leakage evident. It was not too severe, but you would perhaps hope for more given the cost of this screen. Results will vary of course, but this is what we saw from our test sample.

 

Office and Windows Use

 

The PA271W obviously offers a very large 27" screen size, but is combined with an ultra-high 2560 x 1440 resolution. This is a 16:9 format of the same resolution used in a 30" screen (2560 x 1600) so the pixel pitch is even smaller and text size is very small. The screen offers a 0.230mm pixel pitch which is smaller than the 0.270mm of the 24" PA241W and probably smaller than most people will be used to. As a result, text is pretty tiny but after a while you do get used to it. It may actually be too small for some users so if you prefer larger fonts you may want to try and see a pixel pitch like this in person before you make a purchase. Having said that, the massive resolution is really good for office and general use, giving you a really big screen area to work with. It is a noticable upgrade from a 24" 1920 x 1200 resolution, and it's good to see NEC have opted for the high res panel here rather than sticking with a 1920 x 1200 res panel as some 27" models do. For those wanting a high resolution for CAD, design, photo work etc, this is a really good option.

 

The image was very sharp and crisp and text was very clear using the Dual Link DVI interface. There was no D-sub of course here to make a comparison of picture quality. There are plenty of preset modes available from the screen and a massive range of adjustments possible so it's very easy to get the screen to a comfortable setting for office use. The wide range of ergonomic adjustments also made it wasy to get a comfortable position for the screen as you would hope.

 

Above: Close up view of text at native 2560 x 1440 resolution (left) and at 1920 x 1080 (right)

With a resolution this high, some users will no doubt want to know if the scaler chips can handle interpolation well or not. Some may even want to use the screen outside of the native resolution, but be warned, this will impact on sharpness and picture quality. For comparison, I tested the screen in 1920 x 1080 resolution (1080 HD resolution, and popular amongst modern 24" screens). As you can see from the close up macro photos above, the font is very crisp and sharp when the screen is set at its native resolution. It becomes less clear and seems to overlap more pixels when it is trying to scale a smaller resolution onto the panel. This is of course very common for any screen where you use it outside of its native resolution. Although text was perfectly readable and quite adequate when using a lower resolution, I'd obviously recommend using the native resolution wherever you can for optimum results. 1920 x 1080 also feels too big for a screen of this size.

The added USB ports are useful for connecting external devices although it may have been useful to have more than 1 available on the side of the screen. A card reader may also have been useful although I suppose you can't have everything! I personally like an auto brightness feature from a screen so was pleased to see the availability of this option on the PA271W. This feature automatically controls the brightness of your screen during normal operation depending on the ambient lighting conditions in your working environment. It is available via the advanced OSD menu, but cannot be operated when in the SpectraView calibrated mode. This worked quite well with smooth and subtle changes in the brightness of the screen which were not too obvious and certainly not distracting. The ECO modes may also be useful to some users who are energy conscious.

 

Responsiveness and Gaming

The NEC PA271W was tested using the chase test in PixPerAn, a good bit of software for trying to quantify differences in real terms responsiveness between monitors. As a reminder, a series of pictures are taken on the highest shutter speed and compared. The images below show the best case example on the left hand side, and the worst case example on the right hand side. This should only be used as a rough guide to comparative responsiveness but is handy as a way of keeping a constant test of each screen.

 

12ms ISO LG.Display p-IPS (note about G2G response time below)

6ms G2G LG.Display H-IPS

1ms G2G CMO TN Film (Response time mode = Advanced)

16ms ISO LG.Display p-IPS (note about G2G response time below)

6ms G2G LG.Display H-IPS

 

You might note from the above that I've listed the PA271W as having a 12ms ISO response time as opposed to the 7ms G2G which is quoted in the manufacturers spec. This is because by default, the response time compensation (RTC) technology is turned down for this screen. If you enter into the advanced OSD menu there is an option for 'response improve', and I wanted to test it first of all when set to 'off'. I don't think it turns the RTC off altogether when you disable this feature though, but does seem to tone it down a little.

With this set to 'off', the screen shows a fair degree of motion blur but actually not as bad as some non-overdriven models we have tested. While there is a noticeable blur, there is  not really any ghost image behind the moving car which is good. The PA271W shows more blur than the Dell U2711, but is free from the dark RTC overshoot you can see from that model. The reason for this is that the RTC impulse is applied too aggressively on the U2711. It does help improve and reduce motion blur, but introduces this dark trailing which can be fairly noticeable in practice. In an ideal world you want a RTC impulse which removes the blurring and ghosting, but is well controlled so as not to introduce artefacts or overshoot.

The PA271W is a little faster than the 24" PA241W in this test (again PA241W shown without the response improve feature enabled). It was not quite as fast as the 1ms G2G ViewSonic VX2739wm but you would expect that given that the ViewSonic is an ultra-fast gamer orientated screen, and the PA271W is a professional graphics screen.
 

  

For those who do want to game a bit more on the screen, NEC have allowed you to boost the RTC control via the advanced OSD menu. As shown above, there is an option for 'Response Improve', and you can simply turn it on and off. Let's see how it affects responsiveness in practice:

12ms ISO LG.Display p-IPS (response improve = off)

7ms G2G LG.Display p-IPS (response improve = on)

It's not perfect, but there are some improvements when this feature is enabled. The blurring is reduced slightly on the moving car which is good, but it does introduce a slight dark trail artefact as a result of the more aggressive impulse. It doesn't seem to boost the RTC control too much, and the overshoot is very minimal. For gaming, I'd recommend having this option enabled.

 

 

7ms G2G LG.Display p-IPS (response improve = on)

 

3ms G2G Samsung TN Film + 120Hz

I've provided a comparison above of the PA271W vs. our reference screen when it comes to this test, the Samsung 2233RZ. The SM2233RZ is a TN Film based 22" model with aggressive overdrive application, and with its 120Hz technology it is extremely fast and also shows very few RTC artefacts when in 120Hz mode. This also gives you a higher frame rate and smoother movement to the human eye.

The PA271W offers hardware level aspect ratio control. The options are available through the 'expansion' menu and there are options for 'full', 'aspect', 'off' and 'custom' available.

 

Input Lag

As usual I tested the screen in clone mode with a CRT to determine the level of input lag. This is something which can put off some gamers and is a delay between graphics card and monitor output. By hooking up a CRT you can show that  the LCD lags behind somewhat, which can affect users in some situations where they rely on the screen image being as fast as their inputs (e.g. fast FPS shooting games). Often, input lag is very low and probably wouldn't represent too much of a problem in real terms.

 

 

The input lag of the NEC PA271W was mediocre really. We've already said this many times, but remember that this is not a gamer-orientated screen. The average input lag was recorded at 32.5ms, ranging up to 40ms maximum. This was a very similar performance to the 27" Dell U2711 (30ms) and NEC PA241W (26.9ms). It was not as fast as models like the Samsung SM2233RZ (15ms), ViewSonic VX2739wm (9.4ms) or Asus MS246H (6.9ms) as you would expect given those are all TN Film based gaming screens. At 32.5ms, the PA271W is still ok for some average gaming, but you probably wouldn't want to play fast FPS games on it. Then again, you probably wouldn't buy this screen for that use!

 

 

Movies and Video

The following summarises the NEC PA271W's performance in video applications:

• 27" screen size makes it a reasonable option for an all-in-one multimedia screen, noticeably bigger than a 24" model and the same size as some smaller LCD TV's

• 16:9 aspect ratio format suitable for movies and films and provides fewer black borders than a 16:10 format screen

• 2560 x 1440 resolution is more than enough to handle a full 1080 HD resolution (1920 x 1080)

• Digital interfaces support HDCP for any encrypted and protected content

• DisplayPort interface available for connecting external devices, along with a second DVI if you need it. Might have been nice to see HDMI available here as well considering its wide usage for DVD / Blu-ray players and modern games consoles

• Fairly good black depth and contrast ratio helping to ensure detail in darker scenes is not lost. A little behind some other models but still pretty good for an IPS matrix

• No preset modes for 'multimedia' or 'movies' which feature on some more mainstream models. This screen does have several preset modes so you could easily set one up for movies if you wanted. It's common to want a slightly brighter and more colourful image for movies than perhaps you might use for office / colour work, so setting up one of the presets for this would be possible.

• There is no dynamic contrast ratio (DCR) available from this screen which some people do like to use for movies to dynamically control the backlight

• There is a Picture By Picture (PbP) mode available via the OSD if you want to use it for displaying two devices at the same time alongside one another, along with Picture In Picture (PiP)

• Decent response time making it suitable for viewing fast moving images without obvious ghosting or severe blurring. I would recommend setting the 'response improve' feature to 'on' to maximise potential.

• Panel uniformity was excellent, with no obvious backlight leakage from any edge or corner. There was a very slight leakage when viewing an all black image, but not something you can spot in movies.

• Wide viewing angles thanks to IPS panel technology making it suitable for viewing from different positions and for multiple viewers without issue

• Good ergonomic range from the stand which allows you to easily set the screen at a comfortable position for watching movies from various angles and positions.

 

Conclusion

Firstly, you will probably know that this screen comes at a fairly high cost. In the UK the screen retails for ~�1220 GBP, compared with its more mainstream rival, the Dell U2711 retailing for ~�800. We have discussed the reasons for this in quite a lot of detail in this review but you need to remember that this is a screen aimed at the professional market and colour enthusiasts. It has a lot of advanced features and technologies which put it in this niche and result in a higher cost.

 

Performance wise, the NEC PA271W can also justify it's high cost. Colour accuracy is excellent, even out of the box. NEC have provided this screen with a great range of factory calibrated preset modes, and plenty of options to choose from including an Adobe RGB and sRGB emulation mode. Default results were the best we have seen from any screen in fact. The screen offers a hardware calibration option and a 14-bit LUT which can be corrected through the SpectraView packages we have looked at in a fair amount of detail. For high end users this hardware calibration is vital and the screen performs very well when combined with these NEC software packages. If you want even more accurate performance and flexibility, the SV edition of the screen can be purchased for a little more.

 

In other areas, the screen also performed very well. It's ultra-high resolution was well suited to office work and applications where minute detail and accuracy are needed. Viewing angles were wide, response time was actually pretty good and uniformity was excellent. The added functionality of the ColorComp, auto brightness and response time boost are also nice to have available, and worked well. The screen also offers a very good range of ergonomic adjustments and a pretty healthy set of interface options.

 

The only slight criticisms I would have about the PA271W would probably be the average black depth and contrast ratio, the moderate input lag, and the slight backlight bleed which we saw from a dark image. The latter of course will vary from sample to sample, but I'll mention it as really there are very few areas I can pick on which are bad from this screen.

 

Overall it's a very high end and complex screen, with a massive range of options and features which make it ideal for the professional market and colour critical work. The NEC software is also very good and can offer varying levels of calibration, well worth looking in to. Even though the price is high, it is to be expected when you are looking at a screen from this sector, and overall there was very little bad to say about it.