by Oleg Artamonov
03/15/2010 | 09:30 AM
In this review I am going to share with you my experience of testing one of the most interesting, also from a purely practical point of view, monitors selling today. By practical I mean that it does not deliver some unique features at a crazy prize but rather that it offers such a mix of characteristics, price and quality as to make it highly appealing for a specific circle of customers.
The monitor is called NEC MultiSync EA231WMi and it is one of the few products based on an e-EPS matrix that has a native resolution of 1920x1080 pixels (often referred to as Full-HD). In fact, this is the single such model widely available in many cities and countries of the globe and it is the combination of IPS technology with its wide viewing angles (and, consequently, high color accuracy) with the high resolution and reasonable price that make the EA231WMi such an appealing choice for people who are not satisfied with the image quality of mainstream TN-based monitors.
I already wrote about e-IPS panels and will give you some basic facts here. For all its advantages (the most important of which is the lack of color distortions when you don’t look directly at the screen), the well-known IPS technology has one grave downside. It is expensive. One cause for that is the low transparency of S-IPS matrixes. In order to reach an acceptable brightness, they increase the intensity of the backlight, which means more backlight lamps, a more sophisticated power circuit, etc. Alas, monitors with S-IPS panels are only competitive in the small market niche of models for professional color-processing applications where the price factor is often of secondary importance. And this targeting even makes S-IPS monitors more expensive because that market niche has a number of special requirements that increase the manufacturing cost. For example, professional monitors have to be accurately set up and offer a broad range of user-defined settings. Producing “simplified” S-IPS monitors for the mainstream market segment has proved to be of no commercial benefit because such monitors are too expensive for amateurs but not serious enough for professionals.
The main maker of IPS panels LG has developed a solution in the way of e-IPS technology. In an e-IPS matrix, the pixel structure is changed in such a way as to make the LCD panel more transparent and lower the intensity and manufacturing cost of the backlight. LG claims that new e-IPS panels are comparable to TN ones in price. E-IPS-based monitors are still 30-50% more expensive than TN-based ones, yet this difference is negligible compared to S-IPS monitors. For example, the MultiSync EA231WMi sells in retail for less than $600 whereas the 20-inch NEC MultiSync LCD2090UXi, a professional-class monitor with an S-IPS matrix, costs over $1000!
I must confess that the simplification of S-IPS to e-IPS has affected not only price but also image quality. To be specific, the viewing angles of e-IPS matrixes are narrower. When viewed from a side, the picture on such a matrix quickly loses its contrast, becoming whitish. This does not mean that e-IPS is no good for color-processing applications, though. An e-IPS matrix loses only contrast when viewed from a side whereas the competing PVA (both S-PVA and C-PVA) and TN matrixes display a noticeable tonal shift, i.e. a change in image colors. The reduced contrast is something you can put up with when working with images but the tonal shift may be a serious problem. Besides, black becomes slightly violet on S-IPS matrixes when viewed sideways while the e-IPS technology is free from this defect.
The reduction of contrast on e-IPS matrixes can be avoided by means of special correcting film but, unfortunately, this film makes the LCD panel more expensive and is not used often as the consequence. The NEC MultiSync EA231WMi does not have such film, either.
Use the following link for a description of our testing methodology and the equipment we use as well as for a brief explanation of what the specified and tested parameters of LCD monitors mean: X-bit Labs Presents: LCD Monitors Testing Methodology In Depth. If you feel overwhelmed with the numbers and terms this article abounds in, check out an appropriate section of the mentioned article for explanation.
You can also check out the Monitors section of our site if this review doesn’t cover the model you are interested in.
The specified response time is unusually high for a modern monitor. Today’s monitors are mostly specified to be as fast as 8 milliseconds or better, but this one is as slow as 14 milliseconds.
Otherwise, the specs are ordinary enough, considering that the monitor owes its large viewing angles to its e-IPS matrix. It features dynamic contrast technology (although the dynamic contrast ratio is not high), screen height adjustment and portrait mode. The EA231WMi has a DisplayPort, so you can use it with AMD’s new ATI Radeon HD 5xxx series graphics cards as a third monitor (such graphics cards have two DVI outputs and one DisplayPort and all of these interfaces can be active simultaneously).
The EA231WMi has the massive and angular case typical of NEC’s “serious” products and comes in two color schemes: all-black and white-with-a-silvery-bezel. I can’t call this an elegant home model but the design is all right for a work-oriented device.
The monitor has a removable stand that conceals fasteners for a standard VESA mount. Thus, you can hang your EA231WMi on the wall if you want to. The default stand allows adjusting the height of the screen (it is not fixed in the bottommost position and stretches out to its full length when you take the monitor out of the box or lift it up from your desk) and its tilt. You can also turn the screen around into portrait mode.
The two protrusions in the bottom of the back panel are integrated speakers. Their sound quality is expectedly low but the left speaker has a handy headphones connector. Also on the left side of the case there are two ports of the integrated USB hub.
The connectors block includes one more USB port, a DisplayPort, a DVI-D and a D-Sub connector. Why a D-Sub rather than an HDMI or a second DVI-D? I guess that’s because the controller installed in the monitor has only two digital inputs, one of which is for the DisplayPort.
The power adapter is integrated into the case.
The control buttons can be found in the bottom right of the front panel. A small 4-way joystick is used for menu navigation. NEC has been implementing this method of navigation for long but still cannot get it quite right. Sometimes you have to guess the correct way to push the joystick down for it to react well. The Power indicator is integrated into the monitor’s Power button. The small hole to the left of the Menu button is an ambient lighting sensor.
The monitor’s onscreen menu follows NEC’s recently adopted style with five main sections and drop-down lists with subsections.
Two items are interesting in the first section: ECO Mode and Auto Brightness. ECO Mode does not seem functional at first. It only allows to switch between two levels of brightness (the eco-friendliness boils down to the fact that the lower the brightness, the less power the monitor consumes) and would be perfectly useless if it were not for one thing. There is a dedicated button that allows to switch between the preset levels of brightness without entering the monitor’s menu, i.e. instantly. I cannot stop praising Samsung’s monitors for the same feature (under a different name) because it is most handy when you often have to switch between, for example, text-based applications and movies/games. Instead of each time evoking the onscreen menu to adjust the monitor’s brightness according to the current application, you can just press that button.
The Auto Brightness item allows the monitor to adjust the backlight brightness automatically in three different ways: basing on the ambient lighting sensor, basing on the current image (the darker it is, the higher the brightness), or basing on both. You can specify the minimum and maximum limits of the adjustment.
Here is one drawback of the ECO Mode: when you turn it on, the monitor enables the third, combined, mode of brightness auto-adjustment and you cannot turn it off or choose any of the other two modes. Moreover, the automatic brightness adjustment remains enabled when you return from the ECO into normal mode. So, if you don’t want brightness to be adjusted automatically (and there are many reasons why you may not want it), the ECO Mode feature becomes useless. I don’t understand why the developer decided to link one feature to another in such a way.
Besides the ECO Mode, the monitor has a selection of preset DV Modes but they are no good for practical applications. First, you have to enter the menu to turn them on. Second, the image is too sharp in every DV Mode. Their usefulness for games and movies is questionable (because they affect color reproduction, too) and they are completely useless for work.
The second group of settings is about color temperature which comes in five preset modes. You can change three of them to your own taste.
The next group contains various secondary settings: the volume of the integrated speakers, the order in which the inputs are probed for video signal, automatic shutting down, the brightness of the Power indicator, the scaling-up of the image at non-native resolutions, turning off DDC/CI (this interface allows to control the monitor by means of software from the computer it is connected to), and resetting all the options to their factory defaults.
The fourth menu section contains options pertaining to the menu itself as well as to power saving (“IPM”). The latter has nothing to do with the above-described ECO mode. It refers to the monitor’s ability to fall asleep as soon as the ambient lighting is below the specified threshold. The monitor can be woken up by pressing any button except Power and Select. This feature can hardly be useful at home, but may come in handy in the office. If the lights are turned off and there is nobody in the office, the monitor will fall asleep to save on the electricity bill (if someone has forgotten to turn the computer off).
And finally, the last group of settings is informational and generally useless. The colored item tells you how many kilograms of carbon dioxide have not been thrown into the atmosphere because you have been running the monitor at reduced brightness. This setting has the top place in my uselessness chart because brightness should be selected correctly for the comfort of your eyes rather than to save yourself from global warming.
By default the monitor’s contrast is set at 50% and brightness into the auto-adjustment mode. I turned the auto-adjustment off and selected 100% brightness to measure the monitor’s brightness and contrast ratio myself. To achieve my reference point of 100 nits I selected 30% brightness and 37.5% contrast.
The monitor’s max brightness is 290 nits which is even higher than specified by the manufacturer. The contrast ratio is somewhat lower than 700:1, so this e-IPS matrix is as good as modern TN matrixes but interior to C-PVA in this respect. The dynamic contrast mode is not aggressive: the backlight brightness range is not wide, so the resulting contrast ratio is even lower than 1000:1. Well, dynamic contrast is only useful for movies and some people don’t like it even then.
Take note that the results are identical at the default (50% contrast and 100% brightness) and maximum (100% both) settings. It means that contrast has already reached its maximum at 50%. When you increase this setting higher, you don’t make the image brighter but lose light halftones as they begin to be displayed the same as pure white. I don’t know why NEC sets its monitors up in such a way that half the contrast regulation scale is virtually useless, but it is not the first time I see such setup.
The average nonuniformity of black brightness is 7.5% with a maximum deflection of 24.2%. For white brightness, the average and maximum are 5.4% and 16.4%, respectively. As you can see in the diagrams above, there is a cross-shaped brighter spot when the monitor is all black. It is especially bright in the bottom right corner of the screen (this often depends on the particular sample of the monitor, though). This irregularity of brightness won’t be distracting at work. But if you are watching a movie under dim ambient lighting, the corners of the screen are going to look brighter against a dark background.
The gamma curves look neat at the default settings except for the minor brightening of dark halftones (the bottom left part of the diagram). The monitor displays both lights and darks without problems.
The gamma curves do not change much when the brightness and contrast settings are lowered in the monitor’s menu.
As I said above, the monitor makes the image sharp and distorts its colors in the DV Modes. Here is an example: in the Photo mode, which is supposed to be optimized for viewing photographs, the contrast setting is so high that lights are displayed the same as white. I wouldn’t recommend you to use it for viewing photographs if you care about color accuracy.
At the default settings the color temperature does not vary much between the different levels of grays, but the overall tonality is shifted towards greens. This can be easily corrected by manually adjusting the color temperature. Selecting R=100, G=89 and B=99 in the menu, I got a nearly ideal result (the Custom graph above).
The table with color temperature values confirms my words. The variation between the different levels of gray is no more than 100-200 K, which is an excellent result.
The monitor’s color gamut is roughly as large as the sRGB color space but slightly shifted upwards in the diagram, towards greens. As a result, the monitor does not reproduce red, blue and pink-violet hues purely enough, but the difference from sRGB is so negligible that you cannot see it with a naked eye.
The monitor’s specified response time of 14 milliseconds may provoke some apprehensions about its real-life responsiveness.
Indeed, my measurements suggest that its real average response time is 16.7 milliseconds (GtG). This is faster than the responsiveness of C-PVA monitors (e.g. the Samsung SyncMaster F2380 had an average response time of 20 milliseconds (GtG) with some transitions taking as long as 50 milliseconds and more) but the EA231WMi is no competitor in speed to fast 2-millisecond TN-based monitors and even to 5-millisecond ones.
Thus, the EA231WMi is just fast enough for work and movies but may not be good for dynamic games. But if you have a 5- or 8-millisecond TN-based monitor or an old 25-millisecond S-IPS and are satisfied with their response time, the EA231WMi will be practically the same for you.
As you can guess, this model has no response time compensation and, consequently, no RTC-related visual artifacts.
The NEC MultiSync EA231WMi is a very good monitor for people who need high color accuracy, who do not like the narrow viewing angles of popular TN-based monitors, but who cannot afford a monitor with an S-IPS matrix.
Compared to S-IPS, the single notable difference of the e-IPS matrix installed in the EA231WMi is in the viewing angles: when viewed sideways, the image on the e-IPS matrix loses its contrast, getting whitish. However, this effect is no stronger than with TN and PVA matrixes and is not accompanied with a tonal shift typical of these two matrix types. Besides, the vertical viewing angles are narrower than the horizontal ones with TN matrixes whereas they are equal with e-IPS.
Although I did not see this with the few samples I’ve checked out myself, I must warn you that some users have complained about color temperature irregularities of their EA231WMi: when displaying a gray background, the corners of the screen would be greenish or pinkish. Be careful and check your monitor out for this defect. It should be perfectly visible even in the tumult of a computer shop if you fill the screen with gray.
Overall, there is only one serious and uncorrectable flaw I can find with the MultiSync EA231WMi. I mean its rather high response time, of course. But if this parameter is unimportant for you, the EA231WMi will make an excellent all-purpose monitor for home and work, including image-processing applications. It is going to be a real gift for many amateur photographers as an optimal alternative to expensive S-IPS and to cheap but not very color-accurate TN matrixes.