Apple's latest 4K and 5K iMacs support a 10-bit graphics driver on OS X El Capitan, allowing for smoother color transitions, according to German website Mac & i. The 10-bit color output enables 1024 gradations per color channel, a significant increase from 256 with 8-bit depth on previous iMacs.

iMac-10-bit

30 bit pixel depth — 10 bit for each RGB color (Image: cinema5D)

Digital filmmaking news website cinema5D explains the technical benefits of 10-bit color depth for professional colorists, photographers and editors:

Professionals know that 10-bit screen color is the desired color depth for serious color correction. When you work in 8-bit you often see banding artefacts and lose detail on soft gradients which makes editing harder and less accurate.

This is not to be confused with the bit depth of your source files. We all know that working with video DSLRs or other heavily compressed video footage that is limited to 8 bit color depth gives you less options during grading and 10 bit, 12 bit or even 16 bit color photos and videos are better. On the screen side 10 bit is the desired depth to let you view the end result without gradation steps.

The new 10-bit color depth reportedly only works within the Preview and Photos applications for now, but other third-party software should eventually take advantage of the technology. The 2014 5K iMac also supports 10-bit color depth on OS X El Capitan, according to these reports.

Related Roundup: iMac
Buyer's Guide: iMac (Caution)
Related Forums: iMac, OS X El Capitan

Top Rated Comments

keysofanxiety Avatar
82 months ago
Why Apple go to all this trouble with amazing technology and then cripple it by shoving in a 5400RPM drive is beyond me. You've made 11 billion dollars profit in 3 months. Just make SSDs standard in all your computers already.
Score: 44 Votes (Like | Disagree)
dasmb Avatar
82 months ago
The average human eye registers... 7 bits of color. By using ten bit color you go from one bit of color you can't see to three bits of color you can't see (per channel, per pixel). So I am asking my graphics processor to process 9 bits per pixel that make no discernible difference in the quality of the image. Why not leave it at 8 bits and maybe OpenCl can make use of the unused graphics card clock cycles/processing?
Well, given that we can ALL see gradation issues with 8 bit, they must be on to something right?

The secret is that reproduction of light intensity by pixels, as well as the capturing of light intensity by photosensors, is linear. Half the value, half as much light.

The eye, on the other hand, does not process light information linearly. We tend to be able to pick out detail in medium dark areas better than those in very dark or very light areas.

As such, if you were to use 7 or 8 bit color, the eye can easily see incremental changes in color in the middle brightness band, whereas incremental changes in very bright parts of the band are nearly impossible to discern.

By increasing the bit level, you better cover this gap in the perceptual gamut of the eye. You could get the same value in 7 pixels by applying a mapping function equivalent to the eye's discrimination to the hardware pixels and to the light signal in memory.

However, you'd find this used a LOT more resources and was incorrect far more often than simply pushing some extra bits. That's because mapping is computationally expensive, every eye is different and it's unlikely a mapping function on commodity hardware and in commodity software is going to meet your exact need.
Score: 20 Votes (Like | Disagree)
redscull Avatar
82 months ago
I don't think anybody I know should buy the base model.
Correction: Nobody should buy the base model. And they shouldn't even sell it because that dupes unwitting customers. Any version with a 5400 disk is truly a crappy computer. That disk is a bottleneck that cripples an otherwise excellent machine. Whatever dollars you save buying that version, they aren't worth it. The dollars you're still spending are being spent on junk at that point.

It seems like every iMac discussion going forward, no matter what cool feature it is they added, is going to quickly diverge into complaints about how crappy the disk is and how that completely overshadows anything else they do.
Score: 17 Votes (Like | Disagree)
keysofanxiety Avatar
82 months ago
And SSDs do not yet have the same capacities. Just attach an external SSD and be happy already, eh? :)
If the fix to the performance problems on a £1500 iMac is to run the OS through an external drive — well, I think that gives a stronger argument than I can ever articulate.
Score: 16 Votes (Like | Disagree)
redscull Avatar
82 months ago
What you're actually complaining about is that you think its too expensive to buy the drive you want and you expect it for less.
No. That's not it at all. The point is that the Apple brand is associated with a certain amount of quality and prestige. They refused to jump on the netbook bandwagon way back when because netbooks, whether $200 or $2, were garbage. At any price, the user experience was so terrible that it would be cruel to subject a person to them. Apple recognized this and held themselves to a higher standard.

They no longer hold themselves to that higher standard. They are now selling a computer which truly is garbage. Their 5400 disk iMacs are so frustrating to use that the experience damages their brand and reputation. And non-tech consumers just don't know enough to avoid this trap. They'll buy the base model because it's cheapest or simply in stock, and assume that no matter what, they can rely on Apple to give them a solid product. That's what Apple is known for, after all. But they will feel swindled as soon as they start using it. It offers a horrible user experience right out of the box.

As an Apple fan and shareholder, I do not like where this is headed. I don't think it's in the best interest of Apple to degrade its reputation by sacrificing the quality of their products. I want them to keep being awesome, not become yet another computer maker willing to sell whatever cheap drivel they can.
Score: 15 Votes (Like | Disagree)
keysofanxiety Avatar
82 months ago
Apple invested in the supply chain in astronomical numbers. Until the stock of the 5400RPM drives are gone, and the cost of a sizable SSD comes down, and Apple can corner that part of the market for their own longevity/sustaining, we won't see it. 2 years ago, I paid ~$370 for a 480GB SSD. I've never worried about running out of space.
Yep, I know the feeling. 4 years ago I paid £240 for an OCZ 240GB SSD that had read/write speeds of 150MB/s either way. I buggered it after I stupidly enabled TRIM. Luckily they later replaced for a 256GB.

Now I can buy a 500GB Samsung 850 EVO SSD for less than £120. Apple could easily get that far cheaper, that's not in question.

5400RPMs in 2015, with those specs, and at that price, is a joke. You can't even swap it out for an SSD. No appreciation of longevity, or value for money. Raise the price by £100 if you have to, and throw in a 256GB PCI-e SSD on the base model. Just don't offer 5400RPM drives for Christ's sake.
Score: 15 Votes (Like | Disagree)

Popular Stories

Upcoming Products 2022 Feature

Gurman: Apple Preparing 'Widest Array of New Hardware Products in Its History' for Fall

Sunday January 23, 2022 10:32 am PST by
Apple is working on a number of new products that are set to launch this fall, and Bloomberg's Mark Gurman says that it will be "the widest array" of new devices that Apple has introduced in its history. In his latest "Power On" newsletter, Gurman explains that Apple is working on four new flagship iPhones (iPhone 14, iPhone 14 Max, iPhone 14 Pro, and iPhone 14 Pro Max), an updated low-end Ma...
macbook pro 14 16 2021

Three Months After Launch, Apple Still Struggling to Meet Demand for Redesigned 14-Inch and 16-Inch MacBook Pro

Monday January 24, 2022 7:12 am PST by
Three months after their launch, the 14-inch and 16-inch MacBook Pros continue to experience high demand and seemingly short supply, with shipping dates for both models stretching into multiple weeks in several of Apple's key markets. In the United States, the baseline 14-inch MacBook Pro with the M1 Pro chip is estimated to ship in three to four weeks, promising an arrival by at least...
General Dropbox Feature

macOS 12.3 Will Include Cloud Storage Changes Affecting Dropbox and OneDrive

Tuesday January 25, 2022 3:31 pm PST by
Dropbox today announced that users who update to macOS 12.3 once that software version becomes available may temporarily encounter issues with opening online-only files in some third-party apps on their Mac. In a support document and an email to customers, Dropbox said it is actively working on full support for online-only files on macOS 12.3 and will begin rolling out an updated version of...
Questionable Design Decisions

Apple's Most Questionable Design Decisions in Recent Memory

Sunday January 23, 2022 2:59 am PST by
Apple has always emphasized the depth of thought that goes into the design of its products. In the foreword to Designed by Apple in California, a photo book released by the company in 2016, Jony Ive explains how Apple strives "to define objects that appear effortless" and "so simple, coherent and inevitable that there could be no rational alternative." But every once in a while even Apple...
Apple Watch Red Yellow Green Feature 1

Apple Launches Black Unity Braided Solo Loop With 'Unity Lights' Watch Face

Wednesday January 26, 2022 6:05 am PST by
Apple today announced the Black Unity Braided Solo Loop for the Apple Watch, as well as a new downloadable watch face, to celebrate Black History Month. Following the launch of the limited edition Black Unity Apple Watch Series 6 and Sport Band in 2021, Apple today launched the Black Unity Braided Solo Loop as part of its celebrations for Black History Month this year.Apple is launching a...
att gigabit internet

AT&T Bringing $180/Month 5-Gigabit Internet to 70 Cities

Monday January 24, 2022 9:20 am PST by
AT&T today announced the launch of upgraded AT&T Fiber plans, which support speeds of up to 5 Gigabits for some customers. There are two separate plans, one "2 GIG" plan and one "5 GIG" plan, available to new and existing AT&T Fiber subscribers. According to AT&T, the new plans are available to nearly 5.2 million customers across 70 metro areas including Los Angeles, Atlanta, Chicago, San...
intel vs m1 max chip purple

Benchmarks Confirm Intel's Latest Core i9 Chip Outperforms Apple's M1 Max With Several Caveats

Wednesday January 26, 2022 8:56 am PST by
Benchmark results have started to surface for MSI's new GE76 Raider, one of the first laptops to be powered by Intel's new 12th-generation Core i9 processor. Intel previously said that its new high-end Core i9 processor is faster than Apple's M1 Max chip in the 16-inch MacBook Pro and, as noted by Macworld, early Geekbench 5 results do appear to confirm this claim, but there are several...
ios 15

Apple Releases iOS 15.3 and iPadOS 15.3 With Fix for Safari Bug That Leaks Browsing Activity

Wednesday January 26, 2022 10:00 am PST by
Apple today released iOS 15.3 and iPadOS 15.3, the third major updates to the iOS and iPadOS 15 operating systems that were released in September 2021. iOS and iPadOS 15.3 come almost two weeks after the release of iOS and iPadOS 15.2.1, minor bug fix updates. The iOS 15.3 and iPadOS 15.3 updates can be downloaded for free and the software is available on all eligible devices over-the-air in ...