Diglloyd publications have included the viewing pleasure of UltraHD images for about 18 months now (~3840 wide, 8.3 million pixels). These will fit comfortably on a 5K iMac in their full glory, with room to spare. And thus make me reevaluate my top-end publication size, because a 5K display is 14.7 million pixels, or nearly the entire resolution of many APS-C cameras! Incredible.
A 4K UltraHD 3840 X 2560 image will easily fit onto an iMac 5K display. The 8.3 million pixels will leave another 6.4 million pixels unused! Click for larger.
Bruce Z writes:
Do you think the iMac 5K screen will be able to be profiled as readily as the NEC screens are famous for?
5K images will look great, but we will still need to have the monitor tweak-able with a display calibration system to get the most out of those pixels.
MPG: Any display can be profiled, the question is whether true calibration can be done, or just crummy faux calibration.
Calibration is designating a target output, then adjusting the display itself to match that target as closely as possible, ideally with < 1 delta E accuracy using 14-bit adjustments internal to the display. Contrast that with 8-bit numbers on a video card which are adjusted (mangled) to achieve something “sorta accurate”—that is faux calibration. Ask yourself how 2/3/4/5-bit numbers (dark tones) could ever be properly adjusted: there is no dark gray having value 13.7, only a choice of 13 or 14 (crudely stepped/rounded). OS X graphics drivers are still only 8 bit, not even 10 bit, which makes matters worse.
Once a display is calibrated properly (or faux-calibrated), its actual performance—what it actually produces for the designated target (gamma, grayscale, color, etc)—is characterized with a display profile (profiling).
All iMacs including the new iMac 5K can be profiled, but cannot be calibrated. So the iMac will still have faux calibration along with a shiny screen which is not good for print matching. Beautiful to behold, but not a professional-grade tool, especially over time and temperature changes. For professionals doing work where color accuracy matters (and consistency over time matters), the NEC PA322UHD is a far superior choice.