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A second look at the MacBook Pro LED-backlit screen

LED backlight in Apple's new 15-inch MacBook Pros as a lot going for it, but …

A few days ago, Ars reviewed the new 17" MacBook Pro. Most of that review also applies to the new 15-inchers, but there is one aspect to the latest incarnation of the 15" MacBook Pro that warrants another look: the LED-backlit screen.

When I started up my new 2.2 GHz 15" MacBook Pro this morning, I wasn't immediately struck by the brightness of the screen. Sure, it was brighter than the screen of the PowerBook I was replacing, and maybe even a bit brighter than the CRT that still decorates my desk, but not by a huge margin. Then again, it was a cloudy day, so no sun to wash out the image on the screen. However after it had gotten dark, I launched an investigation into rumors that the iSight now has a 1.3 megapixel resolution. (It doesn't. Too bad.) Initially, the iSight images were too dark to be useful. So I thought I'd increase the screen brightness, thinking that maybe that would illuminate my face. Did it ever. I almost had to squint because of the barrage of photons sent my way. You can actually video conference in complete darkness, with only the display to light your face. So, yes, it's bright. Apple says that the brightness is the same as the previous model, but remember, I'm upgrading from a nearly four-year-old PowerBook. Also, the screen goes to full brightness immediately. No warming up. The keyboard backlighting is also very bright and is a bit on the purple side.

The next thing I wanted to know was whether the yellow cast observed in some photos of the new MBPs meant that the new screens have a different color temperature than the old ones. They don't. Visual inspection shows no color cast, and looking at the color profile for the screen with the ColorSync Utility shows that the native white point is identical to that of the previous-generation of MBP 15" screens. That would be standard 6500K or D65—the color of daylight on an overcast day. However, looking at the screen from an angle makes the image brown-yellowish. I was a bit worried about the viewing angles, but it's not as bad as I had feared. If you sit back a bit and adjust the screen so it's perpendicular to your line of sight, you're in good shape. When leaning in, however, you'll look at the corners of the screen at enough of an angle to introduce color shifts.

The black level is very good for an LCD screen: it's not entirely pitch black, but it's getting there. The one thing I don't like so much is that the very top of the screen (10 to 15 pixels) is brighter than the rest of the display. But the top of the screen is the best place for this flaw, as it's normally hidden by the menu bar and when playing video, the problem area will likely end up in the letter boxing for wide screen content, as the aspect is 16:10 while wide screen video is 16:9.

Really good LED-backlit LCD screens are supposed to have a wider range of colors (the gamut) than regular LCD displays with cold cathode fluorescent lamp (CCFL) backlights, but cheap LED-powered displays can have a worse-than-usual gamut. Apple says the new screens are identical to the old ones, which is hard to believe considering the fundamental change in underlying technology. So I was very interested to see how the information in the color profiles of the new screen compares to that of its immediate predecessor. If you look at the images closely, you'll see that the triangle that encompasses the gamut of the display is slightly bigger for the new MacBook Pro: it extends farther into the yellow part of the spectrum. However, compared to the sRGB profile, the change doesn't amount to much.

So although Apple's claim that the new screens are identical to the old ones isn't strictly true, it's not hard to see hard to see why they would say that.

Channel Ars Technica