The iMac’s 5K Retina Screen Is Spectacular

(Deanna Fitzmaurice/Yahoo Tech)

You’ve never seen anything like the screen on the new iMac with Retina 5K Display.

This iMac has more pixels. More than any all-in-one computer ever sold. More than any monitor ever sold. (Dell has announced a 5K monitor, but it won’t be available until December.) And it really makes a difference.

(David Pogue/Yahoo Tech)

The rest of the iMac is good, too. The body looks just like the previous 27-inch iMac’s: It’s made of smooth, sculpted aluminum. The jacks are all in a tidy row in the back (headphone, four USB 3.0 slots, two Thunderbolt 2 jacks, memory-card slot, and gigabit Ethernet).

(David Pogue/Yahoo Tech)

The speakers are hidden (they fire downward from the front edge), but the sound is surprisingly crisp, rich, and clean. A wireless Bluetooth mouse and keyboard are included. The screen tilts, although you can’t adjust the height.

But then there’s that big new feature: the “5K” display (so named because it has more than 5,000 pixels across).

How many pixels is that altogether?

14.7 million. That’s seven times as many pixels as on a 1080p HDTV set. It’s 67 percent more pixels even than a “4K” Ultra HD television. It’s four times as many pixels as the existing 27-inch iMac’s screen.

This screen packs in 218 pixels per inch — so tiny, so close together, that you can’t distinguish them at normal viewing distance. (Frankly, I can’t distinguish them right up close, either.)

But pure quantity of pixels doesn’t make anyone’s life better unless they’re good pixels. And on this iMac they are terrific pixels. This screen looks good from any angle. The glass is glossy, but not nearly as reflective as in the old days. Text is so sharp you could cut your finger on it.

The colors are superb. The blacks are really black. You want to swim in it, to inhabit it — or, at the very least, to do all your photo and video editing work on it.

And that, by the way, is the whole point of this computer: photo and video work.

The value prop
The Retina iMac goes for $2,500. In the world of 5K, that’s actually a bargain; the upcoming Dell 5K monitor also costs $2,500, but that’s without a computer.

Apple’s new 5K screen, on the other hand, comes with a free, cleverly hidden Mac. As on previous iMacs, this one seems to have ridiculously thin edges — but it’s an optical illusion. The guts are hidden inside the bulge in the middle of the back.

(David Pogue/Yahoo Tech)

They’re nice guts, too. The base model comes with a fast chip (3.5 GHz quad-core Intel Core i5), 8 gigabytes of memory, a terabyte of storage (Apple’s hybrid Fusion drive, part traditional hard drive, part flash memory), and a high-horsepower video card (AMD Radeon R9 M290X with 2 GB video memory).

If you have enough money, or if the generous corporation that employs you does, you can upgrade those components. For example, you can get an iMac with a faster chip (4.0 GHz quad-core Intel Core i7), 32 gigs of memory, 3 terabytes of disk space, and a beefed-up video card (AMD Radeon R9 M295X). For $3,750.

It’s wild, isn’t it? In the beginning, Steve Jobs imagined that Apple’s Mac line would include only four models: laptop and desktop, consumer and pro. The iMac was supposed to be the consumer desktop computer.

With these specs, and this price, a well-configured iMac is no longer a consumer product. This machine is clearly designed for the high end.

Professional TV and film editors can use an iMac to edit the latest kind of footage: 4K footage, which is so extremely high-resolution that very few TV sets can even display it. They’ll have every pixel visible and still have enough screen area left over for tool palettes and control bars.

This baby is all about photography, too. It’s true that even a 5K screen doesn’t have enough pixels to show every dot in a photo from a pro SLR (which might have 6,000 or 7,000 pixels across). Even on this screen, you still have to view those photos at a reduced size.

But you won’t have to shrink them nearly as much — and if your camera is anything shy of a pro model with nutso megapixels, you may be able to see the entire photo without zooming out.

(Here’s a photo that would fit entirely on the iMac’s screen. Click to see how well it fits the one you’re looking at right now.)

And when you’re not editing video, well, all that real estate is like having a two- or three-monitor setup — on a single screen. You can keep multiple programs open at once without a lot of overlapping.

Don’t forget, meanwhile, that a 27-inch expanse of glowing image is, itself, quite a treat. This machine makes a fine TV and movie player for an apartment, bedroom, or kitchen, even if you’ll have a hard time finding 4K-resolution video to exploit it. (I did test Netflix’s experimental 4K video clips. They looked wonderful.)

Horsepower
The new iMac is very fast. When you do email, Web work, writing, design, layout, finance, Photoshop, HD video editing … well, the computer will be waiting for you, not the other way around.

Even so, the new iMac isn’t appreciably faster than last year’s. It handles games with aplomb but, at this resolution, not at the frame rates hard-core gamers would like.

And I was surprised to encounter some video playback stuttering (skipped frames) in Final Cut Pro X when I was editing 4K video, which is supposedly one of this machine’s specialties. It usually didn’t repeat itself on the same clip, but still.

The wet blanket
Now, a 5K computer beats a lower-K computer any day. If you win the new 5K iMac at a church bake sale, by all means take it.

But there are several reasons why the new iMac isn’t for everyone.

First, of course, the higher resolution the screen, the more expensive it is. $2,500 may be a bargain among 5K monitors, but it’s still $800 more than the regular, 27-inch, non-Retina iMac. That’s right: For the price of the 5K-er, you could buy a regular 27-inch iMac, a beautiful new iPad, and still have enough money left over for a week of celebratory dinners at Applebee’s.

Second, a Retina display does wonders for text, video, and high-res photos. But on webpages, low-resolution images, like ads and some photos, can look truly horrible.

Here’s how the top of nytimes.com looks on a Retina display. Compare the sharpness of the word “Times” … with the ad to its right.

Yuck.

Third — rats! — you can’t use the iMac 5K as a monitor for another Mac. For years, laptop fans have adored that feature; they can come home, hook up to an iMac, and enjoy a much bigger screen. But no Mac except the 5K iMac itself has the video circuitry required to blast 14 million pixels to the screen 30 times a second — so that feature has gone away on this iMac.

The dream machine
Apple loves doing this kind of thing: creating a cutting-edge, expensive, first-of-its-kind showcase luxury stunner. The new iMac is clearly impractical for the masses, but it’s a sure indication of what’s to come as these technologies become mainstream in the coming years.

In the meanwhile, here it is: the world’s first 5K computer. It’s great for professionals and anyone who’s having a really good year. For everyone else — well, it sure gives us something to look forward to.

<Correction: This article original misstated the price of the cheaper iMac.

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