Readers know I am not a fan of the iMac for professional use for a variety of reasons having to do with workflow, ports, color matching, etc. But....
Apple’s announcement of a 5K iMac (5120 X 2880, 14.7 million pixels) stops me in my tracks and makes me lust over the screen, for the screen is how we see things on a computer. The 5120 X 2880 resolution behaves like a 2560 X 1440 display (pixel doubling) in user interface terms, but can be scaled to other sizes.
Apple probably had to do some custom work to support a 5K display because even Thunderbolt 2 falls well short on bandwidth (cannot drive a 5K display, which needs ~45 MB/sec bandwidth). But in the all-in-one iMac, custom is fine; no standards need to be followed for connectors and so on. The iMac can only drive 4K for external (additional) displays.
But here’s the kicker: the 5K iMac starts at $2499. So it’s like buying a groundbreaking display and getting a computer for free: the professional-grade NEC PA322UHD 4K display will list at $2999 ($3249 for BK-SV model), and while that is my intended screen on my 2013 Mac Pro for color matching and image evaluation, for sheer viewing pleasure the iMac 5K offers a far larger number of viewable pixels.
With up to a 4 GHz quad-core CPU, it’s gonna be fast, but what a shame it can’t go to 64GB memory (32GB seems to be the limit).
The iMac 5K has clear limits which make the 2013 Mac Pro a better choice for high-end users:
- 32GB memory limit (64GB or 128GB with Mac Pro).
- No 6/8/12 core variants.
- Single high performance GPU with 4GB max memory (Mac Pro can have two GPUS each with 6GB).
- Two Thunderbolt port, presumably on a single Thunderbolt bus (versus 6 ports on 3 busses for Mac Pro).
- More likely to fail with rigorous usage, if for no other reason that less robust cooling and built-in display.
- MPG ordered the iMac with 8GB so as to get 32GB of memory at OWC, saving several hundred dollars.
- The internal 1TB SSD (“flash storage”) is the way to go for power users; add the OWC Thunderbay for extra storage.
- Get the fastest CPU, which compensates in part for other factors. It should outperform all 2013 Mac Pro models for many if not most common tasks, because most tasks use only a few CPU cores.
- The fastest GPU is less important than getting a large SSD and faster CPU for most users and uses.
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.
But there is an “out” by adding a 4K display externally:
Simultaneously supports full native resolution on the built-in display and up to 3840 by 2160 pixels on an external display