The color gamut of a display can be calculated in many different ways, and there
is no industry standard method. Therefore unless the exact method used to calculate
the values is specified it is difficult to compare values between different displays.
NEC calculates the Color Gamut Size and Coverage specifications as a 2D gamut area
in CIE 1931 xy or CIE 1976 uv colorspace using measurements from a very precise
spectrophotometer. The display color gamut is compared to that of a reference gamut,
such as sRGB, AdobeRGB, or NTSC (1953).
The Gamut Size specification is the total relative display gamut area and includes
any colors outside the reference gamut expressed as a percentage. In other words
it is the area of the display color gamut triangle vs. the area of the reference
color gamut triangle, and does not take into account if the gamuts actually overlap
or not – it is just the ratio of the total areas
The Gamut Coverage is the relative display gamut area contained inside the reference
gamut expressed as a percentage. In other words it is the area of the intersection
of the display color gamut triangle and the area of the reference color gamut triangle
vs. the entire area of the reference color gamut triangle. The maximum possible
coverage value is 100%.
The official specifications for several SpectraView displays are shown below calculated
using both CIE 1931 xy and CIE 1976 uv colorspaces:
The CIE 1931 xy colorspace is the more popular and widely recognized colorspace, and engineers are used to using this for calculations and charts. But it does not give equal area representation to different colors—in particular, the size of the green area is overemphasized, but the blue area is underemphasized.
The CIE 1976 uv colorspace attempts to correct for this representation problem by scaling the chart so that colors are more equally represented. This means CIE 1976 uv is technically more useful for comparison purposes, but not as popular due to legacy usage and recognition.
No. The NTSC (National Television System Committee) specification for color television encoding was finalized in 1953. Part of this specification defined the color gamut for the system as three color primaries (red, green and blue). The gamut that these primaries actually encompassed was huge and well beyond the limitations of the TV camera and display technology at the time, so it was never actually adopted for TV broadcast applications. A much smaller and more achievable color gamut—known today as SMPTE-C or SMPTE 170M—was officially standardized and adopted by the TV broadcast industry in the 1960s.
The original NTSC 1953 gamut specification has lingered in various charts and tables and has been resurrected in recent years as a large color gamut with which to compare device gamuts, even though it has nothing to do with modern TV applications.
It is very important to note that anyone who is doing any kind of video editing or production on their display monitor needs to use a color gamut as close as possible to SMPTE-C or sRGB, and not NTSC 1953. This can be done by either using a display monitor with a color gamut close to sRGB, or by using a wide gamut display monitor together with video editing software that is color management aware, or via the sRGB emulation mode on the display.
These saturation controls normally apply to all colors equally. but with a wide-gamut display, the red and green are typically much more saturated than sRGB, while the blue is typically very close to sRGB.
Because of this, using this control can cause blue to become under-saturated. Using these controls may also interfere with the SpectraView calibration because they may not be able to be reset by applications other than the control panel.
The recommended and default re-calibration period is every 2 weeks. But some users working in highly critical color applications may calibrate their displays every few days.
The Validate Calibration feature can always be used to verify the display’s white point and Intensity and determine if the monitor needs to be re-calibrated. Always remember to allow the monitor sufficient time to warm up and reach optimum color performance before performing any color critical work or calibrating the display.
A brand new display typically needs to be calibrated more often than one that has been in use for several months.
The Mini DisplayPort to SingleLink DVI adapter will be able to show full native resolution on all displays except the LCD3090WQXi. The Mini DisplayPort to DualLink DVI adapter is required on the LCD3090WQXi in order to display the full 2560x1600 native resolution.
Note: It is currently (as of OS 10.5.7) necessary to use the SingleLink adapter when calibrating the LCD3090WQXi with SpectraViewII. Therefore both adapters are required. See the SpectraView ReadMe file for the SpectraView software for more details.
The profile associated with the Primary display can be easily checked in Photoshop using the following steps:
1. Open the "Color Settings" dialog in Photoshop from the "Edit" menu.
2. Open the "Working Spaces RGB" listbox.
3. Look near the top of the list for an entry starting with "Monitor RGB - ". The text shown after this is the description tag of the ICC profile that Photoshop is current using for the primary display. DO NOT SELECT THIS. Only confirm it is listed and is the same as the profile shown in "ICC Profile" in the "Information Summary" window in SpectraView.
Currently all web browsers that are color managed, such as Safari and Firefox 3, only use the ICC/ColorSync profile for the primary display for color correction. This means that even if a browser window is moved to the secondary display, it is still (incorrectly) using the color correction for the primary display.
Also Safari assumes that all images that do not have an embedded ICC profile are unmanaged and are not color corrected. Only images that have an ICC profile are corrected. Firefox 3 correctly assumes that all images that do not have an embedded ICC profile are in sRGB colorspace.
Internet Explorer does not support color management on Windows.
FireFox 3 supports color management, but it must be manually enabled (see below). All images with no embedded color profile are assumed to be sRGB and are color-managed. Note that only the primary display is correctly color-managed.
Safari is color-managed and enabled by default. Images with no embedded color profile are not color managed. Note that only the primary display is correctly color-managed.
Follow these steps to enable color management:
1. Type "about:config" in the address bar of Firefox 3.
2. Click thru to the confirmation page and find the following line in the list: "gfx.color_management.enabled".
3. Double click that line so it says "true."
4. Restart Firefox 3.
The information shown in the Color Management tab on the Advanced Display Properties in Windows can sometimes get out of sync and incorrectly report which ICC profile is associated with each display.
A more advanced control panel is available from Microsoft for Windows XP which is much more reliable for checking the assigned monitor profile. On the Microsoft website, search for “Color Control Panel Applet.”
1. When the OSD is not displayed, press the "Reset."
2. In the "Picture Mode" menu, use the left or right buttons to switch between sRGB and Programmable modes.
The Programmable mode is the wide-gamut mode that was calibrated by SpectraView. The Standard mode can be used for any custom settings not relating to sRGB or SpectraView.
The following are the main changes made to the LCD2490WUXi2:
1.The color gamut has been modified slightly to more closely match that of sRGB. The sRGB coverage is 96.7% (versus 93.5% on the LCD2490WUXi) in CIE xy.
2. The contrast ratio has been improved from 800:1 to 1000:1.
3. The maximum typical luminance has decreased from 400 to 320 cd/m².