
27” Retina math - shawndumas
http://www.marco.org/2012/08/30/retina-27-math
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stephen_g
That's pretty cool - I hope they bring these out soon!

But, since I hate incorrect terminology, this is wrong:

    
    
        4K = 3840×2160
    

Some TV manufacturers incorrectly use the term 4K like this, but the way it's
been used for the last decade in the film industry (and is specified in
standards like the DCI spec) is that 4K refers to images with a horizontal
resolution of 4096 pixels [1] (the number of pixels vertically changes to
accommodate different aspect ratios - the pixels are always square).

The TV industry is using 3840 because it has four times the resolution on
1080p. I don't think there are any specifications for this resolution, so
there's no official term. I've heard it called QuadHD or 4xHD though.

1\. There is one exception, which is 3996x2160 (1.89:1 aspect) but all the
others are 4096.

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arrrg
All this Retina talk makes me sick. Apple doesn't have this technology under
control. They screwed up.

My first Retina screen had horrible image persistence problems. The
replacement from Apple now has the same problems. Coincidence? In the Munich
Apple Store I had the opportunity to check four machines (of the seven they
had standing around), all four had the exact same problem.

Apple can't build them now, they really shouldn't try to build more of them.

~~~
shawnz
Cry me a river. That's the price of early adoption. "Retina" displays at sizes
larger than 4" have only been available for less than 6 months.

~~~
slurgfest
I think it is valid to point out the flaws of a product which is regarded as
market-leading. For example: why aren't other companies offering similar
products? Could in part be because of problems such as this.

If we can't be a little honest about a company that is (I believe) bigger than
Wal-mart then I don't know what company WOULD be strong enough to withstand
mild criticism.

~~~
enraged_camel
The flaws are real, but they are blown way out of proportion with comments
like "Apple doesn't have this technology under control. They screwed up."

~~~
arrrg
I’m sorry, but selling a product with a defect like that is just unacceptable.
There are no ifs and buts about that. That’s just how it is.

It would be great if they could fix this issue. I would be overjoyed. However,
they seem to be unable to, now even going so far as talking the defect down.

~~~
enraged_camel
>>I’m sorry, but selling a product with a defect like that is just
unacceptable. There are no ifs and buts about that. That’s just how it is.

Unacceptable to who? The products in question are selling by the millions.
Clearly, the market finds them _very_ acceptable. In the grand scheme of
things, what you think is largely irrelevant.

~~~
chucknelson
arrrg obviously has an ax to grind about Apple in general or just has some
irrational, intense hatred for retina screens. From the replies I've seen,
reasonable discussion is out of the question. "Illegal"? Please.

~~~
arrrg
Ignoring the defect screen, I love everything about the machine. I think it’s
pretty plainly the best laptop on the planet right now (at least for me
personally). I would much rather Apple fix this than having to give back my
MBPr. But I can't accept a defect screen. It's quite simple.

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frankus
I'm curious as to why OP keeps insisting that current Thunderbolt ports can't
support a QFHD (3840 x 2160) display.

Thunderbolt layers a few lanes of PCIe with a DisplayPort 1.2 signal.
DisplayPort 1.2 supports QFHD at 30 bits/pixel and 60Hz.

Of course you'd be limited to one display per port, and I'm not sure whether
that much bandwidth on the DisplayPort lanes would crowd out the PCIe traffic.

Alternatively (as anyone who bought Macs in the 90's can attest), Apple has
never been particularly reluctant to introduce a new interconnect when it was
convenient for them.

Obviously if they simply pixel-doubled their current 27" panel it would be far
beyond Thunderbolt's capabilities, which may be where the "Thunderbolt can't
support Retina resolutions" idea originated.

~~~
wmf
In theory the display signal would need 12.8 Gbps leaving 7.2 Gbps for PCIe
traffic, so it's not obviously impossible. It's not clear whether Thunderbolt
controllers can mux and demux over 10 Gbps worth of DP though.

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incision
I'm impressed with the way Apple succeeds at branding things like relative
pixel density.

I expect there have to be some, but I'm having a hard time recalling similar
schemes from other companies that weren't met with ridicule.

~~~
tvon
I don't know. If Lenovo, Motorola and Microsoft had teamed up and said "HiDPI
is the future, we're putting it on our flagship devices and making it a
primary feature of Windows". If they had done that, and implemented it well
(eg, most people say it's gorgeous), then they could have named it "Windows
ThinkDensity MotoDisplay Technology 8" and that is more or less what we'd be
calling it.

Point is, it may be something that is conceptually simple and technologically
practical but if company X bets their flagship product on the tech and ends up
being the driving force in the mainstream adoption of said technology, then I
think they get to brand it.

~~~
arn
Microsoft's version of Retina is called ClearType Full HD Display. Non retina
is called ClearType HD Display.

~~~
Evbn
You forgot a few TM and R superscripts. Not having these is one of the main
distinctions of Apple's marketing copy.

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ChuckMcM
Interesting math, 3840 × 2160 at 32 bpp (ARGB32) is just about 32MB per frame
(3840 * 2160 * 4) / (1024 * 1024). At 60 fps that is 1.92GB/second of pixel
churn. Perhaps I'm just getting too old but to me that is an impressive amount
of data to throw around.

~~~
bigiain
I just did those same calculations and got the same somewhat boggling numbers
(actually, I only assume 24bit pixels at the panel and got ~24MB frames).

I then wondered how the OS & Window Manager & Applications & video driver &
memory bus & pci bus & video card deal with the respective parts of their
chunks of a data stream that big… (Then managed to realize I've got work to do
before heading down the google-research-of-interesting-thing rabbit hole…)

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gojomo
As I age, I find all my old monitors are upgrading in place.

I think someday even a 640x480 laptop screen will someday be a 'retina'
resolution for my unaided eyes.

