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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.
But seriously, yes, LCD (and any decent LCD mfgr) will spec the color bit depth of a panel. A really good mfgr (NEC, LG, Samsung) will have gamut charts available to OEMs and possibly end users. But if Apple chooses not to share, or worse just lies about it, there's not much you can do other than try to do some independent research to figure out what panels Apple uses, then contact the panel mfgr to (try to) get some specs.
everything in moderation
It's 6 bit per color in a rgb scheme, making it 18 bit or 262,144 total.
I'm aging rapidly, I bought a new game and had no idea if my machine was good for it.
I admit I have no idea how to figure out how many colors there are with 6 bits per pixel...but I did find this website which talks about 8bit and 6bit LCDs: http://compreviews.about.com/od/multimedia/a/LCDColor.htm
Pretty much any monitor advertised as 16.2 million colors is using a 6 bit panel with hardware dithering. Those advertised as 16.7 million colors tend to be 8 bit.
6-bit colors? In 2008? What were they thinking? The trend is towards 10 bits. At 6 bits, gradients look awful; false edges appear. Go into Photoshop, generate a single color gradient, and then "posterize" to 64 colors to see what this looks like. Yuck.
Dithering won't help; it puts noise into a nice, smooth gradient.
I admit I have no idea how to figure out how many colors there are with 6 bits per pixel...
2 states for each bit (on or off); 6 bits per pixel; 3 subpixels per pixel (red, green, blue)
(2^6)(2^6)(2^6) = 262,144
No, the article just wasn't clear. It actually means 6-bits per color channel per pixel. In other words, 18-bits per pixel instead of full 24-bits per pixel. And the reduction from 2^24 to 2^18 does indeed reduce the number of colors from about 16 million to 262,144 - a reduction of about 98% of the entire color space.
And as someone who owns a 18-bits per pixel monitor, trust me, you can tell when working with static imagery. Maybe not when playing games or playing movies, but you can tell. The little gradients on Slashdot look terrible on that monitor. It helps that it doesn't do any form of dithering, but even on my cheap Acer laptop that also only does 18bpp, you can clearly see the dithering.
Since Apples are frequently used for photo work and print work, using only 6 bits per color channel is simply unacceptable. Coders probably won't care, but graphic artists most certainly will.
You are in a maze of twisty little relative jumps, all alike.
They make the claim that the "display" supports "millions of colors". And by display, they mean something that has 290 cd/m2 brightness and a 160 degree viewing angle -- which could hardly be referring to the GPU/video card.
The wheel is turning, but the hamster is dead.
Technically, you could only define 32 colours of those 64 (from a total palette of 4096!), the other 32 were actually the same colour but at half the brightness, hence the name of the display mode: EHB - Extra Half-Brite. This was very useful since you could use that extra bit-plane as a shadow-plane, and most palettes had dark and bright versions of the colours anyway.
Of course, this doesn't make it any less superior, just saying...
c++;
Mod parent up. This is absolutely true. I'd estimate that the vast majority of LCD panels on the market are 6-bit screens. Whether you are buying Benq, LG, Dell, Viewsonic, it doesn't matter. Most of them are 6 bit.
They are cheaper, and they have faster response times.
8-bit LCD panels are almost a niche specialty 'pro product' in today's market, and unless you went out of your way to buy an 8 bit screen odds are you took home a 6-bit TN panel, advertised as showing "16.2 million colours" without even knowing it.
Its not just Apple. Although they seem to have gone beyond marketing deceptiveness to outright lies and deserve to be taken to task about it.
But don't for a minute think all those free Dell monitors bundled with low end PCs are anything better. Hell, even the ones you can pay to upgrade to aren't often anything better than 6-bit.
Most people dont realize (hell, nobody does) that 6 bit panels (as opposed to 8 bit panels) do not lose the 2 MSB; they lose the 2 LSB. As a result,instead of the LSB being a digial 1, it's valued at a digital 4. They are fully capable of displaying the full 24 bit color palette, but they have problems when the image is very dark. To illustrate the point, when the image is Full White (R,G,B=255,255,255) with an 8 bit panel you may see the signal swing from 254-255. On a 6bit panel the signal will swing from 251-255 since the LSB is now 4. You will only notice this on certain shades of grey, and you will need to be looking for this effect since the issue is very subtle to begin with, and then its very hard to notice unless somebody knows EXACTLY what you are seeing. Apple just went from a PVA panel (better viewing angle (180), better contrast (1000:1), crappy response (8ms) ) to a TN panel (average viewing angle (165), average contrast (700:1), but awesome response (2-3ms)). Nothing to see, move on.
There is no better laptop screen, because no one makes one. You can increase the resolution by paying extra, but you're still getting the same cheap TN crap that everyone uses and that Apple is getting sued for advertising as capable of displaying "millions of colors."
Crap TN panels are slowly but surely taking over the desktop space too. It's hard to find a non-TN panel under 23" these days, and even many 24" and all 27" panels use the sucky technology.
Unfortunately, Americans still largely drive tech trends, and we rarely care about anything but "big and cheap." (We say we do, but then we actually still buy "big and cheap.")
This isn't about the MacBook suit, this is about 20" iMac desktops.
Incidentally a guy (Mac user) on our forums ran some tests on his Thinkpad and found that it does indeed have an IPS display. So although TN screens may be common on laptops they're not ubiquitous.
I realize that. I was responding specifically to the inaccuracy in the parent post.
Incidentally a guy (Mac user) on our forums ran some tests on his Thinkpad and found that it does indeed have an IPS display. So although TN screens may be common on laptops they're not ubiquitous.IBM made several ThinkPads with IPS panels 2-4 years ago, although none were produced in large numbers. The 14" and 15" IPS screens are no longer being made. The only one I know of still being sold is the X-series tablet, which has a 1440x900 12" IPS screen that I believe is also now out of production.
TN was just too big and cheap for IPS to survive. There was no money for the panel makers in producing a tiny quantity of $100 more expensive laptop screens for the few buyers with enough basic perceptivity to tell the difference.
Actually, there were two 6-bit modes on the Amiga - EHB, as described, and HAM (Hold And Modify), which caused the pixels defined as colors 32-63 to be defined as "the color of the pixel to the left, but with its (R|G|B) value replaced with ...", thus allowing for all 4096 colors on-screen at once, but usually with a slight fudge-factor, depending on your image and how you arranged your 32-color palette.
And that's not getting into the later chipsets, which mostly just added bits... (:
Let's start with, it's multiplicative, not additive. That's 255^3, not 255*3. This is because, as you mentition later, the eye combines all three subpixels into a new color.
If you interpert color as a wavelenght of light as opposed to relative excitment of the three colored cones in your eye, then yes. But no one thinks of that definition. Instead, the obvious usage is 'colors preceived'. Even when you talk about color of a pure wavelength, you can only interpert it as combinations of your three cones.
So, even if one were to concede all your points, these aren't really 1920x1280x24 displays are they then. Because that 1920x1280 resolution has to get shortchanged for the dithering. So you can say that Apple lied about the resolution instead of the color if you like, but it's awful pedantic.
I know people who paid a lot more to get a camera with a Foveon sensor, actually. While I might be unable to notice the quality, they (and their clients) can. And you better believe they would be pissed if they ended up with a Bayer filter instead.
If you want to say that the difference is small, and unnoticible to most people, so that is the optimal thing to make, fine. I respect that, and agree with you. But this is flagrant false advertising. A 1920x1280x24 screen was advertised and not delivered. Bitch about Apple's behavior just like any other major company's.
Your ad here. Ask me how!
Try the following exercise:
1. Find a new 20" iMac (or laptop, or other machine with a crap TN panel). Find a good IPS panel such as the one on a 24" iMac. Put them side by side.
2. Open your favorite image editor.
3. Create a diagonal gradient starting with black and ending with 50% pure blue or green
4. The hard part: tell me with a straight face that you can't see the dithering.
At typical viewing distances, subpixels are small enough to dither with reasonable effectiveness. Full pixels aren't, at least where the color transitions are subtle.
What the hell is the complaint about? Even a screen with an 8-bit DAC is only capable of displaying 766 colours - each subpixel can show 255 brightnesses of three distinct wavelengths of light (as each subpixel can show the same black this makes 766, not 768). ... This whole thing is stupid. It sounds like people nitpicking advertising, without actually being aware of the technical concepts involved the image display process.
... you pass judgement with authority, but nowhere in your post do you indicate that you've actually looked at a new 20" iMac. So I'm gonna call you out and say that you're full of bullshit.
Interesting
If there is no visual difference between a good 18-bpp display and a 24- or 36-bpp display, then why are they dirt cheap and considered inferior by everyone who has ever owned or used one for image processing work?
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)."
No offense intended, but I can't believe in this day and age that people who are otherwise generally well-versed in computers and computer peripherals are still not even aware of this specification for LCD screens - which is probably the most important one.
Everybody gets so fixated on response times and viewing angles, but none of that amounts to a hill of beans without color rendition and accuracy. The most important specs to look at on any LCD screen are bits per pixel and gamut. Contrast is also useful to know if you also know black level threshold. Without that, though, contrast ratio is useless because it's much easier to make an LCD screen brighter than it is to make one darker, and LCD screens these days are by and large capable of much more brightness than would ever be usable. A contrast ratio of 10,000:1 is meaningless without knowing the starting point for that range.
Unfortunately, most manufacturers make the specs that are actually important almost impossible to find. Even a lot of manufacturers who could brag about these things - because their screens do all the right things in color rendition and accuracy - choose not to. Dell, for example, is probably the largest manufacturer of 8bpp Super-IPS screens with wide color gamuts. Their higher-end screens, which are still pretty cheap relative to most screens marketed towards professionals, are among the more capable out there. But I have never seen Dell actually try to make this argument - I have never seen them argue that colors on their monitors are more vibrant and true-to-life (to use the marketing-speak that they'd probably go with), even though they could.
The reason is that people don't seem to know or care. And they should. You're looking at a screen in some cases almost every waking hour you have (if you're like me and work on computers, then go home and switch on your laptop), and many people are using them for things like photo editing or home video production. People should be demanding good color rendition.
It's almost shocking that Apple, of all companies, does not provide 8bpp panels across their entire line. At the very least, given their reputation as a manufacturer of computers for creative professionals, they should be making it clear which screens are 8bpp panels and which ones aren't. And they should be publishing their screens' gamut as well.
Whether you are buying Benq, LG, Dell, Viewsonic, it doesn't matter. Most of them are 6 bit. ... But don't for a minute think all those free Dell monitors bundled with low end PCs are anything better. Hell, even the ones you can pay to upgrade to aren't often anything better than 6-bit.
For those interested in looking up the monitors, here is a handy guide that gives you the inside scoop on most of the Dell flat panels. Also why the the 200x, 240x, and 300x series monitors get the loving they do and were worth the extra dollars.
+++ UGUCAUCGUAUUUCU
I believe this has already been tested in court (I think against Palm?), and that the 'dithering defense' was duly defeated. So the perceptual definition may be irrelevant to the cast at hand.
For one, there are laptop screens that use other panel types. For example LG Display makes the LP201WE1 which is a full 8-bit laptop LCD panel.
Also it is easy to get non-TN panels for desktop displays, you just have to be willing to pay more. For example the LG L1910S is a 19" S-IPS monitor. However, it's going to run you like $350, not the $150 you may be accustomed to for monitors that size. Same deal with larger panels. Yep, you can get 24" TN panels, and you can get them for an extremely good deal. Just $350 will get you a cheap KDS 24" TN panel. However, you can get a nicer panel if you like. $600 gets you a BenQ FP241VW which has an A-MVA panel. Need even better? Ok the NEC 2490WUXi has an amazing LG H-IPS panel in it, and tons of professional features (like hardware calibration with 12-bit per channel look up tables), however it'll run you about $1100.
So it isn't that you can't get good displays, it is that most people don't chose to. For them, they'll take the cheap TN panels.
The reason Apple is getting in trouble is twofunavaliable
1) They DO charge a hefty premium for their devices.
2) All the dick waving they do about things looking better. They talk about the "rich vivid color" and in the case of the Macbook talked about how much better of a display it was. Ok, fair enough, but if you are going to tell people you are giving them a quality display, it'd better actually back that up.
So if Dell wants to sell crap screens, it works out ok because they don't ever seem to indicate anything about them. Even their better screens are only marketed as "extra bright". However if they started talking about how much better color they gave, well then they'd better actually do that, or there'd be trouble.
Unfortunately, that isn't a good indicator anymore. This is in part because companies are deceptive, but mostly because retailers don't know what they are talking about. At any rate, just do a little searching around and you'll find 6-bit TN panels that are listed on a site as "16.7 million colours". The reason is that the site isn't even checking, they just put that for ALL monitors.
It also goes the other way too. I am thinking about getting an NEC 2690WUXi which is a pro monitor. It is, of course, an 8-bit panel. NEC verifies this, you can check the specs on the LG panel it uses too. Ok, one would expect this for the price. However, it seems not all the resellers know this. One lists it as "more than 16 million" and another as 16.2 million. Again, it isn't that they think it is a 6-bit panel, it is that they just list that for all monitors.
So really the only way to be sure is to find out what panel a monitor uses, then look up that panel. Thus far, I've never seen a panel manufacturer lie about it. For 6-bit panels, they even say 262k colours.
The only other guideline you ca use is price. If there's a big price jump, chances are you jumped panel quality. For example you find 24" monitors in the $350-400 range, and then they suddenly jump to $550+. Sure enough, you go from TN to VA when you do that, and thus also from 6 to 8 bit. This isn't foolproof, but generally if there is a big jump and the monitors are "expensive" all of a sudden for a given size, you are getting an 8-bit panel.
everything in moderation
I use one of these exact machines on the weekend and in the last few weeks I've been having serious eye strain. When I come home during the week and use generic 17" LCDs or my 19" CRT the need to rest my eyes constantly goes away by about Wednesday, but it comes back every weekend when I use that 20" iMac. Seems like a pretty direct correlation. It could be something else like the lighting in the room there, but I'm wondering if anybody else who has used one of these had noticed unusual eye troubles after prolonged usage.
I use the database at flatpanels.dk. Just input the main part of the model number of the monitor, and you'll get what panel(s) it comes with. There should be other databases around as well. Avoid TN, S-IPS/S-PVA/etc. is probably good enough. But do check reviews, as the panel isn't the whole story, the backlight is important too, as well as a few other factors.
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
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.
This actually means that your monitor is displaying a large range of color outside of the sRGB colorspace. While the colors on your screen may appear more vivid, they are not an accurate representation of the color contained in the images you are looking at (unless you have setup your image workflow to correctly work and display images in the Adobe colorspace). The result is drastically LESS accurate color than you would get on a CRT.
Unfortunately, the onlydetermining factor in response time is the LCD panel itself. DVI/VGA cables, screen resolution, and signal refresh rates won't make a lick of difference, any more than standing on one leg when you turn on the microwave will cook your food faster.
Asus, Viewsonic, Samsung and many others have 2ms LCD monitors out nowadays that should set you in good stead for gaming, and prices are as always dropping rapidly.
There are no 8-bit notebook panels (with the sole exception of some 17" models), and most TN panels (which make up the lion's share of the market, because they're the cheapest) are 6bpp, too.
But hey, don't let the facts get in the way.
No 14" Dell notebook has ever had an 8-bit panel, ever. Give me the model number of the LCD and I'll point you in the right direction.