HP LP2480zx - DreamColor - 24" LCD Monitor Using Manual

Using the HP DreamColor LP2480zx
Display with Apple Mac Systems
The HP DreamColor LP2480zx professional display provides an extremely wide color gamut and a
highly accurate color performance that exceeds that available with most other LCD displays. But
instead of merely presenting this wide gamut to the user, this display has the ability to emulate five
specific color spaces that are contained within its color gamut:
 sRGB (used in general purpose computing, web-focused imagery, and consumer photography)
 AdobeRGB (used in professional photography)
 DCI P3 (used in digital cinema production and post-production)
 Rec.709 (used in high definition video production and post-production)
 Rec.601 (used in standard definition video production and post-production)
In addition, the display provides a Full color space which utilizes the display's full native gamut and a
User color space which can be can be used to create a custom color space. All color spaces can be
customized by the user including the ability to modify the color primaries, white point, luminance, and
gamma (tone response). The display can be switched on-the-fly between all of these color spaces and
the user can interactively modify a color space as desired.
The display's ability to either switch color spaces or modify an existing color space on-the-fly presents
a challenge to both the Mac OS and Windows operating systems as they were not designed to
support this capability. As a result, some manual interaction is required at the operating system level
when switching color spaces.
In addition, assumptions made by current versions of the Mac OS regarding gamma can lead to
reduced performance and must be manually compensated for to get the full performance out of the
display. This white paper is designed to explain these issues and provide suggested workflows to get
the most out the HP DreamColor LP2480zx display.
ColorSync Profile Creation
When a display is first connected to the Mac, the OS will use ColorSync to read the display's EDID
(Extended Display Identification Data) information and generate an .icc display profile. This profile
includes many items including a unique device identifier and the device's color primaries, white point
(or color temperature) and gamma. It is important to recognize that the profile can include not only
the device's native primaries, white point, and gamma, but also a desired set of values. If these
values are included the host graphics system must use a look up table (LUT) to translate between the
desired values and the display's native values.
Current versions of the Mac OS add the desired values of a 6500 Kelvin white point (also known as
D ) and a gamma of 1.8 to all .icc display profiles. The rationale for inserting and utilizing these
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values instead of native values is to provide a consistent display experience regardless of the display
connected to the system. While this behavior certainly simplifies life for the user, setting all displays to
the same effective response (gamma) and white point can result in the display having a noticeably
poorer accuracy than could otherwise be provided. This is especially for LCD displays.
As compared to other LCD displays (which use fluorescent or white LED back or side lighting), the HP
DreamColor LP2480zx uses an RGB LED backlight which allows it to use not only a D white point,
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but to adjust the individual LED's intensity to provide a different white point when working in either a
pre-press or digital cinema environment. For example, the pre-press industry prefers a 5000 Kelvin