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MacBook Pro, Thousands of Colors

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Re: MacBook Pro, Thousands of Colors

#101

Post by jhickner »

GHFigs wrote: post #44
bcl wrote: post #15

Interesting. The Apple MacBook Pro website makes no distinction between the models as to the color support. They all say "millions of colors", and as someone who doesn't deal with colors for a living I would expect them to have identical support.

Technically, a 6-bit display can display all of the same colors that an 8-bit display can. What it can't do is display all of them at the same time . Edit: Why all the drive-by downvoting? This is true to the best of my knowledge.

This is actually kind of an important point. I don't know what you're being downvoted for. The upshot is that you really only notice the 6bit/8bit difference on large, smooth gradients.

Re: MacBook Pro, Thousands of Colors

#102

Post by jerf »

SwellJoe wrote: post #30

So how does one tell whether a monitor is 6-bit or 8-bit?

I went a-Googling for that before I saw your message, and here's the best thing I found. (A surprising number of 404s and forbiddens on most test pattern images.) This article [1] has a test image: http://static.photo.net/attachments/bboard/00G/00GkGu-302804... which has a grey gradient across the bottom. Zoom in (Firefox zoom is fine), and then look very closely at the pixels. If you see a dither pattern in most of the cells, you've got 6-bit. If it's smooth and unpatterned, you've got 8-bit.

I have 6-bit, but it's also higher res. Dithering is less of a problem in that scenario. But having seen it clearly, now I understand why you shouldn't do video-intensive work on this sort of display.

1: http://photo.net/digital-darkroom-forum/00GkGu

Re: MacBook Pro, Thousands of Colors

#103

Post by jws »

jws wrote: post #87

Without dithering, 6 bit LCDs produce 191 colors. 8 bit LCDs produce 767 colors. If you want more than 767 colors you will be using dithering. I think where people get confused here is the naive dithering where a group of 3 pixels (one of each color) are logically grouped together gives your the 252k and 16m numbers, but there is no reason that is the only desirable solution. Consider sub-pixel rendering of typograph…

So far, on large areas I can see a difference between #404040 and both #3f3f3f and #414141 on the new 15" MacBook Pro.

That rules out a naive 6 bit display. I think. The application of color profiles can could cause some regions of to have one-to-one mapping even if there aren't enough output codes available to cover the inputs, but I think with the 4:1 difference I can rule that out.

Re: MacBook Pro, Thousands of Colors

#104

Post by mhb »

jasonlbaptiste wrote: post #17
jonknee wrote: post #8

Alternate headline choice: Man with ability to research decides not to and is disappointed in purchase but offered full refund

Alternate comment: How's about commenting on the actual substance and not whining about the headline? Sure, he's asking for a pony in some ways, but they're making pro machines with displays that don't do what they say or anything "pro" for that matter.

It's not just the headline. Who makes a purchase decision base on a product being called "pro"? It must be very confusing for him when he visits a supermarket and encounters words all over the place like "new", "improved", "better", "more", "bigger"...

Re: MacBook Pro, Thousands of Colors

#105

Post by marbletiles »

randallsquared wrote: post #95
catch23 wrote: post #85

Earlier quoted context omitted.

At the minimum, it's faulty marketing on Apple's product. They shouldn't state that it supports millions of colors when it actually doesn't. Just like the CRT monitors that are 17" but only 15" viewable... sometimes that stuff doesn't change until someone files a lawsuit.

It "supports" millions of colors; it just displays some of them with multiple pixel tricks. Which is probably fine with me -- I haven't seen a comparison where I could tell the difference without blowing the pixels up.

The difference leaps out at you if you've done any sort of colour work at all. I can even see in the gradients on the Finder window toolbars.

Re: MacBook Pro, Thousands of Colors

#106

Post by JimmyL »

randallsquared wrote: post #95
catch23 wrote: post #85

Earlier quoted context omitted.

At the minimum, it's faulty marketing on Apple's product. They shouldn't state that it supports millions of colors when it actually doesn't. Just like the CRT monitors that are 17" but only 15" viewable... sometimes that stuff doesn't change until someone files a lawsuit.

It "supports" millions of colors; it just displays some of them with multiple pixel tricks. Which is probably fine with me -- I haven't seen a comparison where I could tell the difference without blowing the pixels up.

I agree. Most people don't know how LCDs work, don't know what dithering is, and wouldn't know what 6bit or 8bit meant if their life depended on it. To these - the majority - of people, "millions of colors" is "millions of colors", and any losses by dithering be damned.

They would ask "if I looked at my monitor, could it show me 'millions of colors'?" to which the one-word answer is "yes". If you had some time, you could expand it to be "yes, but the majority of those are done by this process called dithering, which is when..." and the person you're talking to has lost interest and/or gotten confused. To them, color is color, and they don't care about dithering since it's not visible to them.

This is who marketing is designed for. When most people here see an ad for a system, they immediately skip all the marketing bits and go to the stats, and from that get a good mental idea about the performance of the system, where the bottlenecks will be, etc. When "average" people see an ad for a system they look at the ad copy that says "will launch Word in half the time", decide that that's what they need, and buy the thing.

Ad copy caters to, and explains in context for, the lowest common denominator. If you're not that, then you should be looking elsewhere (at the fine print, the stats, the asterisk at the bottom of the page, etc.) to draw your own conclusions.

Re: MacBook Pro, Thousands of Colors

#107

Post by jws »

jws wrote: post #103
jws wrote: post #87

Without dithering, 6 bit LCDs produce 191 colors. 8 bit LCDs produce 767 colors. If you want more than 767 colors you will be using dithering. I think where people get confused here is the naive dithering where a group of 3 pixels (one of each color) are logically grouped together gives your the 252k and 16m numbers, but there is no reason that is the only desirable solution. Consider sub-pixel rendering of typograph…

So far, on large areas I can see a difference between #404040 and both #3f3f3f and #414141 on the new 15" MacBook Pro. That rules out a naive 6 bit display. I think. The application of color profiles can could cause some regions of to have one-to-one mapping even if there aren't enough output codes available to cover the inputs, but I think with the 4:1 difference I can rule that out.

Here is a little web page I tossed up to help people screen LCDs. http://jim.studt.net/lcd-sleuth/

It will make a table with cells whose text is just slightly off of the background. You can stare are them and explore the limits of your visual system and your computer's display. (No one will be able to see all of the text on any statically adjusted display.)

Additionally, on this MacBook Pro I looked at a greyscale gradient which I have used over the past and decided it was poorly distributed, so I ran through the color calibration (expert mode) in the Displays preferences pane. I ended up with a much better distributed gradient, but I introduced hue distortion so I didn't keep it. But there seems to be room for an improved profile.

Re: MacBook Pro, Thousands of Colors

#108

Post by duskwuff »

greendestiny wrote: post #100
randallsquared wrote: post #95

Earlier quoted context omitted.

It "supports" millions of colors; it just displays some of them with multiple pixel tricks. Which is probably fine with me -- I haven't seen a comparison where I could tell the difference without blowing the pixels up.

Thats the least compelling definition of supports millions of colours I've ever heard. So did my EGA display adapter in the 80s then. I'd be furious if I bought a 6-bit monitor in this day and age and it wasn't spelled in giant letters all over the thing.

You must be furious pretty often, then - because the vast majority of LCDs sold today, with the exception of a few expensive high-end displays, use 6-bit color.

(This is 6 bits per channel, not 6 bits per pixel, by the way.)

Re: MacBook Pro, Thousands of Colors

#109

Post by duskwuff »

jws wrote: post #87

Without dithering, 6 bit LCDs produce 191 colors. 8 bit LCDs produce 767 colors. If you want more than 767 colors you will be using dithering. I think where people get confused here is the naive dithering where a group of 3 pixels (one of each color) are logically grouped together gives your the 252k and 16m numbers, but there is no reason that is the only desirable solution. Consider sub-pixel rendering of typograph…

You are confused. "6 bit displays" have 6 bits of color data per channel, and hence can display 2^18 (262,144) colors without dithering. I'm not sure where you're getting 191 and 767 from.

Re: MacBook Pro, Thousands of Colors

#110

Post by Skeuomorph »

jmillikin wrote: post #79
jm4 wrote: post #25

Earlier quoted context omitted.

That's not entirely fair. The specific information he was looking for is not made available to the public by Apple. He was only able to find the information after getting the model number for the display and checking with the vendor. There was no way of knowing exactly which display was used without access to a MacBook Pro because that's not information made public by Apple, either. It's an awfully roundabout way of…

Apple advertises it as being able to display millions of colors despite the fact that it really only displays 262,144. A 6-bit display is capable of displaying more than 6 bits of color information, using a technique named temporal dithering. For an example, open this image on a 6-bit display: http://imgur.com/BeVicl.png >. If the display could only display 262k colors, the squares would look identical.

Thank you, as this puts paid to anyone here saying there's no visible difference except to pixel peepers.

(Well, assuming one is comparing on a true 8 bit screen.)

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