2007: Has Apple been shortchanging MacBook and MacBook Pro buyers ever since the first Intel ‘Books shipped? That’s what Fred Greaves and Dave Gatley think.

13″ MacBook specs claim millions of colors.

Apple claims to support “millions of colors” on the displays built into the 13.3″ MacBook, 15.4″ MacBook Pro, and 17″ MacBook Pro. Here’s what their website says:

15″ and 17″ MacBook Pro specs claim millions of colors.

What Greaves and Gatley contend is that Apple is actually using LCDs that are incapable of displaying millions of color, and that this causes the banding, sparkling, and graininess some users are complaining about. (This is only in notebooks. Apple’s iMacs and freestanding displays have genuine 24-bit LCDs.)

Theoretically we’re dealing with 24-bit video on all of today’s Macs – 8 bits of red, green, and blue combine to create 16,777,216 colors. However, it seems that all of today’s notebook LCDs only support 6 bits per color channel, which means that these ‘Books can only display 262,144 colors.

However, there’s a catch. An LCD pixel isn’t a single spot. It’s a square composed of three side-by-side red, blue, and green crystals. By using adjacent crystals on the right and/or left (sort of borrowing them from the pixel next door), we can effectively display 7 bits per channel. That’s 21-bit color, which means that using clever programming these “6-bit” LCDs can actually display 2,097,152 colors.

That qualifies as “millions” in my book.

By using the pixels above and below, we’ve got 8 bits of color per channel and the 16 million plus that Apple claims.

Further, it seems that Apple has no choice in the matter. According to postings on ars technica, nobody builds 8-bit-per-channel LCDs that Apple (or anyone else) could be using in their notebook computers. Although the video circuitry supports 8 bits per channel, none of the available LCDs displays more than 6 bits per channel.

My question isn’t whether Apple will be able to win, as I’ve just demonstrated that mathematically they can make their case. Even if a judge doesn’t see it that way, the end users aren’t going to end up with 8-bit-per-channel displays in their existing ‘Books. Nor are they likely to see much money – remember the class action suit over CRT sizes that resulted in the plaintiffs receiving only a $13 rebate coupon that could be applied to a new monitor purchase or a $6 refund?

Only the lawyers will get rich.

The question is how long has Apple and the rest of the industry have been using 6-bit-per-channel LCDs on notebook computers while claiming to display millions of colors.

Oh, and one more thing: Does it really matter? Is a quarter million colors good enough, regardless of what the lawsuit contends?

Further Reading

• Millions of Colors vs. Thousands: What’s the Difference?, Dan Knight, Mac Musings, 2008.04.07