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By default, the monitor has 65% contrast and 59% brightness. To achieve a 100nit white brightness I selected 22% brightness and 25% contrast. I want to remind you that I use the 100nit settings only as a reference point for comparing different monitors at roughly similar settings. In reality, the comfortable settings will depend on your personal preferences and on the intensity of lighting in your room (100 nits is the normal screen brightness for working with text in a well-lit room).

Judging subjectively, I could find no fault with the monitor’s setup quality. Color gradients are reproduced superbly regardless of the contrast setting (gradients look striped on many monitors as soon as you choose settings other than the default ones).

The SyncMaster 275T uses new backlight lamps with improved phosphors which are commonly referred to as Wide Gamut Cold-Cathode Fluorescent Lamps (WG-CCFL). This endows the monitor with a color gamut much larger than the standard sRGB that a majority of LCD and virtually all CRT monitors offer. The influence of the radiation spectrum of phosphors in the backlight lamps on the color gamut was described in our earlier article called Contemporary LCD Monitor Parameters: Objective and Subjective Analysis.

I used calibrator data to build a color gamut diagram for the 275T. You can see that this gamut differs greatly from sRGB in the green area and coincides with it on red and blue. Note also that the 275T cannot match the color gamut of the SyncMaster XL20 with LED-based backlighting: the XL20 renders both green and red colors better.

So if you put the 275T next to a monitor with ordinary backlight lamps, you’ll see that the former displays a purer green whereas the latter displays green with a tincture of yellow.

This raises two theoretical problems. First, most images, both photos and videos, are currently adapted to sRGB monitors. It means that if the original image has a color that corresponds to the green dot in the sRGB space (the green dot is a vertex of the color gamut triangle as in the picture above; it is the purest green the monitor with the given color gamut can reproduce) and a color that is higher than the green dot, the latter color will be changed to be the same as the former after the adaptation. Thus, both colors will look the same on an sRGB monitor.

Now suppose this adapted picture is reproduced on a monitor with an extended color gamut. It can reproduce the different colors mentioned above differently, but those colors are now identical in the picture adapted to sRGB! Both colors will still look the same, but more saturated than on an sRGB monitor.

Alas, this problem will be resolved no sooner than monitors with an extended color gamut have become mass products. It is only then that pictures will be originally adapted for such monitors rather than for sRGB. As a matter of fact, many graphics formats allow embedding color profiles so that the user application could adapt the picture to the particular monitor (and the picture will be displayed just as correctly as it is possible, on any monitor). Unfortunately, most programs cannot work with such profiles, except for advanced image-editing software.

Anyway, I guess that many users, and myself among them, will prefer monitors with incorrect but pure colors, i.e. the 275T, to monitors with incorrect and muddy colors, i.e. older sRGB models.

The second problem is that the enlarged color gamut is still described with 8 bits per channel (24-bit color; in 32-bit color each of the three channels is actually described with 8 bits, too). In other words, there is a larger gap between two adjacent color values than on monitors with a smaller color gamut. By the way, you can output a color gradient from black to red, blue or green even on an sRGB monitor and notice narrow uniform stripes in this gradient. This is not a defect of the monitor. It is a defect of the 8-bit color representation. If you divide the monitor’s screen width by the width of one stripe, you’ll have exactly 256 stripes (but if you see wider stripes in the gradient – then this is the monitor’s defect).

As opposed to the previous problem, this ones has both hardware and software constituents. On one hand, it would be good to transfer the monitor’s and graphics card’s interfaces to 10-bit color. On the other hand, software must be able to process this 10-bit color and graphics formats must use it, too. I don’t think this transition will take place anytime soon just because it involves so many changes, although there have already appeared graphics cards that support 10-bit color (e.g. ATI/AMD’s X1000 series GPUs) and professional monitors with a 10-bit DVI input (e.g. NEC SpectraView Reference 21).

The SyncMaster 275T is mainly intended for home use, though, and doesn’t suffer much from that problem. You don’t expect a precise reproduction of color from a monitor that is not actually meant for working with images professionally.

Summing it all, the extension of the color gamut of PC monitors brings about certain problems which are, however, not significant outside the narrow circle of professionals for whom other monitor models are actually intended. For a home monitor, the extended color gamut is always good without any reservations. It allows the monitor to display purer and more saturated colors.

 
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