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New 20" iMac Screens Show 98% Fewer Colors
Trintech points us to an AppleInsider article about another class-action lawsuit directed against Apple Inc. This one claims that the displays on new 20" iMacs are only capable of 6-bit-per-pixel color, 98% fewer colors than Apple advertises. Rather than the 8-bit, in-plane switching (IPS) screens used in 24" iMacs and earlier 20" models, "[t]he new 20-inch iMac features a 6-bit twisted nematic film (TN) LCD screen," according to the article, "which the [law] firm claims is the 'least expensive of its type,' sporting a narrower viewing angle than the display of the 24-inch model, less color depth, less color accuracy, and greater susceptibility to washout." Apple recently settled a very similar class-action suit about the displays on MacBook and MacBook Pro models.
I don't have a Mac, but I do sometimes buy computer monitors. I can understand specifications like the physical size, resolution, viewing angle and (just about) contrast ratio. But do manufacturers publish specs on what colour depth is supported? Is there some quantitative measure of how well a display shows different colours and how wide the gamut is? How can I avoid getting caught out like these hapless iMac buyers?
-- Ed Avis ed@membled.com
Strange, the first case that was "settled out of court under undisclosed terms" seems to have been just two guys. Surely there are more than two photographers who bought macs thinking they would get 8-bit color and later realized it was only 6-bit. I wonder why no class-action was initiated? Since it wasn't though, it seems like Apple is still open to potentially thousands or more lawsuits for this false advertising.
That's what it is, right? They say "millions of colors" when it's really 262k colors. Or is there some precedent that lets a company claim dithering = unique color?
everything in moderation
I work at an Apple shop, I love Apple products, but I'd be happy to tell you how shitty the 20" Aluminum iMac screens are. They really, really suck, and here's hoping Apple finally gets their head out of their ass and puts a quality screen on what should be a quality product.
Thanks for the clarification. I was sitting here and thinking to myself, "That can't bee right. 6-bits of color is how much my RGB Amiga 500 used in 1987 (64 colors)."
So it's 6 bits per color (red, green, or blue) to achieve 18 bits total (thousands of colors). Versus a "real" monitor that can do 24 bits total, aka millions of colors.
Yeah. Definitely false advertising.
Lousy Apple.
Starting to act like Microscrew.
The government is not your daddy. Its purpose is not to raid middle-class neighbors' wallets and give it to you.
It may be weird, but it's also remarkably common. About half the LCDs on Newegg are reported as showing 16m or 16.2m colors, rather than 16.7m (2^24). A far cry from the 280k-odd colors of a 6-bit-per-channel display, but the number they're reporting is based off of the results of a 6-bit panel using dithering. Many cheaper screens from all manufacturers follow this trend, especially those advertised towards gamers. They sacrifice color reproduction in order to get the pixels to twist faster - all of the reported 2ms panels are 6-bit dithered displays, which gives awful color reproduction (not critical for games most of the time, but a big problem for photo/video work). Of course, anything faster than 16ms is absolutely pointless since you're dealing with a 60Hz signal, but that's aside the point. More notably, the 6-bit panels are quite a bit cheaper, as one would expect.
I'm almost positive that my Macbook Pro does this as well; honestly, quite unacceptable for a "pro" machine. It's especially noticeable at the brighter edge of a gradient (ex. the Photoshop color palette).
Most people aren't going to really notice. Dithering is reasonably effective, and it still manages to give the illusion of most of the spectrum (certainly far more than 6-bit/64 levels per channel, rather than 8-bit/256). But at the end of the day it's still an illusion, and the difference IS there.
How are sites slashdotted when nobody reads TFAs?
I'm the guy that you'd find arguing over how much LCDs suck and how much better CRTs are a couple years ago. But my CRT died last month (Mitsubishi 19" Aperture Grille, it was about the best monitor you could get short of the 22" version of the same), and I picked up a Samsung 226CW. There are only two things it doesn't do as well as the CRT:
Absolute black level.
Off-axis viewing degradation.
The color is actually BETTER, DESPITE the 6 bit panel. The reason why 6 bit is not a big deal is because the panel response is so fast that it can temporally dither two colors into one, and you don't even notice that its doing it. For photography, its actually better color reproduction because its more consistent than CRT. On top of that, the "C" model in particular (as opposed to the 226BW) has a 95 CRI backlight, which means the spectrum the backlight produces is much less peaky and closer to natural sunlight. Altogether, the result is more accurate color than I'd get on a CRT. Plus I get 2ms response time so gaming is fine too.
The 226CW may be TN, but its one of the best panels out there. I thought I was going to be more disappointed than I actually was. In fact, I wasn't disappointed at all because it turned out better in most regards, not just "almost as good." It can produce smooth color because spatial and temporal dithering on fast monitors is surprisingly effective, and its actually more accurate because of the better quality back light.
Not that this was an article about CRT vs LCD, but I'm saying that TN panels have become common not just BECAUSE they're cheap but because the good ones (as cheap as they are) are SURPRISINGLY good. Apple may have used a shitty 6 bit panel instead of, say, Samsung's 6 bit panel, but the number of native colors is surprisingly not that big a deal, even if you're a picture-accuracy freak.
(It doesn't excuse them from not clarifying whether it was TN or IPS though, and in fact it pisses me off that no manufacturers are clear on what overall technology goes into their LCDs)
Each subpixel can display one of 64 values, lets say from 0 to 63. However, each subpixel also can change its value over time. During four consecutive clocks, the sub pixel can have two different values. For example, to produce the values 31 1/4, 31 1/2 and 31 3/4, change the value in a pattern 32-31-31-31, 32-32-31-31, or 32-32-32-31. That way, you achieve 253 different values from 0 to 63 in quarter steps. 16.2 million = 253 * 253 * 253.
(Shameless plug) Rather than creating the image yourself, you can also try The Lagom LCD test pages (and try lots of other monitor tests as well).
Avantslash: low-bandwidth mobile slashdot.
False advertising? Where exactly does apple say the iMac's display outputs 'millions of colours'?
The 'millions of colours' option means (and has meant ever since the Mac IIfX) that a 24bit pallete is used rather than a 16bit pallete. How many colours the display natively supports is a completely different matter.
The culprit here isn't Apple, it's every consumer that ever bought a cheap display and priced true 24bit displays out of the low and midrange market. On any platform if you use a '32bit' or '24bit' setting, you're more than likely not going to be getting that resolution (or even close to it) on your display, whoever the manufacturer.
Show me any audio interface which claims to be 24bit or 16bit resolution and I'll show you it's actual SNR. 98% is a also misleading, like audio color perception is logarithmic. A 16 bit audio CD has 99.996% less audio thingamyjigs than a 24bit professional audio card, but strangely they sound about the same to the untrained ear. 'Creative' declared and actually measured noise floors have always been miles off (when you look at the number 96dB, it's a misprint, they actually mean 69dB)
Who would have thought that the 'low end' mac would have a 'low end' display in it. Nobody expects any other low and mid-range machine to bundle with a professional display, so why should apple users just because they edit some fotos from time to time.
Apples to apples, not apples to lemur testicles.
Professional graphic artists, photographers, compositors and video editors should rightly demand a full pallete, but then that's what those pricey cinema displays are for.