A look at the P3 color gamut of the iMac display (Retina, Late 2015)

iMac 27
The Late 2015 Retina iMac includes the first wide gamut display that Apple has made for a Mac, able to reproduce colors well outside the sRGB color gamut. I had questions about the P3 color gamut of the new iMac, so I went over to my local Apple Store to check it out.

Using a wide gamut monitor can involve certain color challenges, which I cover later in this article. I’ve encountered those challenges using a wide gamut NEC PA272w connected to my Mac Pro. Most people haven’t seen those issues because up to this point it’s been a conscious choice to buy a wide gamut monitor. But the P3 display is now built into all of the new 4K and 5K Retina iMacs, so Retina iMac buyers will now be working with a wide gamut display whether they know it or not.

Wait…what is the P3 color gamut?

A lot of people have heard of the sRGB color gamut that most computer displays and mobile device displays are based on, and many photographers and designers know that the Adobe RGB gamut covers a significantly larger range of colors. But this P3 color gamut is less well known; what is it and where did it come from?

P3 is based on the color gamut produced by the xenon bulb used in digital cinema projectors. Hollywood uses P3 for mastering because it’s the final output space of motion pictures delivered to digitally equipped movie theaters. P3 is larger than sRGB by a big enough amount that a display that can cover P3 colors is considered a wide gamut display. Most wide gamut displays today are based on Adobe RGB.

What’s the default display profile of the Retina iMac ?

At the Apple Store I went straight to the first 27″ Retina iMac I saw. The first thing I did was open the Displays panel in System Preferences to check out the list of display color profiles. On many Macs the display profile set by an OS X install is Color LCD. On the iMac I tried, the selected profile was named iMac.

Default profile for the Retina iMac (Late 2015)

Was the iMac profile the correct profile? I selected “Show profiles for this display only” and the only profile left was iMac. As far as OS X is concerned, the iMac profile is the only one that matches up with the display hardware.

Default display profile for iMac (Late 2015) when showing only profiles for this display

What’s the gamut of the iMac display profile?

But what is the size and shape of the iMac profile gamut? Is it closer to sRGB, or P3? For the answer to that, I opened Apple ColorSync Utility. First I clicked on the iMac profile to see the size and shape of the color gamut. Then I clicked the Display P3 profile. They were nearly identical: The iMac default display profile is very close to the P3 color space. This figure shows a top-down view of the 3D plots of those two gamuts side by side…

iMac and Display P3 profiles side by side in ColorSync Utility

…and this figure shows the same plots of those gamuts overlaid in Photoshop with the Difference blending mode, which revealed very little difference:

iMac and Display P3 profiles overlaid in Photoshop with Difference Mode

So the default iMac display profile does seem to be P3 gamut. I’m assuming that the minor differences are because of the difference between the ideal P3 gamut and the actual performance of the panel as calibrated by Apple.

What if we compare the iMac profile to the Color LCD profile that is also found in the list of display profiles on this iMac? The Color LCD profile gamut is much smaller than the iMac and P3 profiles. However, the Color LCD profile is close to the sRGB profile, so I’m not sure why the Color LCD profile is even included with the iMac because its gamut is too small to describe the iMac display.

Gamuts of Color LCD profile and sRGB profile compared to iMac display profile

Color LCD gamut over iMac display profile gamut (left), and sRGB profile gamut over iMac display profile gamut (right)

I didn’t have time to do much testing with real images, but an article at astramael.com (The Wide Gamut World of Color — iMac Edition) does use sample photos to show the tradeoffs between the Adobe RGB, P3, and sRGB color gamuts. That author also tried something that I didn’t: They brought a colorimeter to the Apple Store, hoping to make their own profile and gamut plot of the P3 display. They report that the Apple Store staff did not allow them to connect and run the colorimeter. For that reason, both that author and I are comparing the Apple-supplied profiles that we found on the iMacs themselves. The Apple Store I went to had no problem with me copying screen shots and profiles to my USB flash drive.

Note that for true digital cinema work, just having a P3 color space isn’t enough. The Digital Cinema Initiative (DCI) standard also specifies a gamma of 2.6 and a luminance of 48 cd/m2 or 100 cd/m2 depending on whether you’re targeting movie theaters or television, and there are also various white point standards. The iMac at the Apple Store was set to maximum brightness which is way too bright for digital cinema or print work, so you’ll need to crank down the brightness of the iMac display and probably still have to use a display profiling device to make sure the display is hitting the correct gamma, luminance, and white point numbers for the specific standard you’re targeting.

How does the iMac P3 display handle untagged objects?

One of the challenges of wide gamut displays is that the colors in untagged objects (objects without a color profile) can appear oversaturated. This can happen when the color values of untagged objects are defined in a smaller color space such as sRGB, which is usually the case. When those untagged color values are displayed on a larger gamut display, if their gamut is simply scaled up to match the larger gamut the color values can end up further out than they should be in the larger color space, appearing oversaturated.

I believe I saw evidence of this when looking at the Late 2015 Retina iMac. I looked at things like the colorful icons in the Applications folder and the graphics in the Maps application. I opened the same windows on the iMac and on a 15” Retina MacBook Pro near it. Even when I turned up the brightness of the MacBook Pro all the way, the colors in the iMac screen were much more vivid. Not just “this display shows more colors” saturated, but some colors seemed to have that unnatural “radioactive” glow that’s associated with untagged objects on wide gamut displays. To me this indicates that Apple may not have completely color-managed OS X system elements for wide gamut displays. I see the same effect on untagged objects when my NEC PA272w display is in wide gamut mode.

I hope to hear more about general untagged color handling on this display from anyone who knows more or is able to test it more thoroughly.

As for the Web, it looks to me like untagged image and CSS colors are rendered correctly in the Safari web browser, but not necessarily outside Safari, such as in the Finder. The tweets below explain why untagged colors in Safari are no longer as screwed up as they used to be on a wide gamut monitor: Safari now does the right thing, in that when Safari 9 sees colors without a profile (untagged) it will assume the colors are in the sRGB color space and convert to wide gamut from there. When Safari sees an image that is tagged with a color profile it will continue to do what it correctly did before: use the image’s profile to convert its colors to the wide gamut display profile, in this case iMac P3.

Does the iMac P3 display have an sRGB mode?

Wide gamut displays can be a challenge for developers of games, mobile apps, web sites, and other content targeted for average consumer displays, because of the oversaturation of untagged content that I just described. Colors can appear unnaturally intense if they’re not mapped properly to a wide gamut display.

Professional wide gamut monitors work around the oversaturation problem by providing an option that restricts their gamut to sRGB. Some let you switch to an SRGB emulation mode through a control on the front panel of the display; with others you switch modes using utility software. The Retina iMac doesn’t do it either way, or at least not in any way that I was able to find. When I searched the OS X help files of the iMac for “P3” or “sRGB” nothing came up. In general, the help files for color management in OS X are pretty thin.

If the iMac P3 display doesn’t have a way to emulate an sRGB display, buyers of the Retina iMac should be aware that colors might not display as expected in untagged objects or in applications and parts of OS X that are not color managed. I’m not 100% sure that there is no sRGB emulation mode on this display, but that’s how it’s looking. If you have more information on this, please post in the comments.

You may sometimes see a suggestion to open the Displays system preference and select the sRGB profile. That is not going to help, because that’s not how display profiles work. A display profile describes the color behavior of the display, but it can’t change that behavior. So choosing the sRGB profile can’t and won’t make the monitor display the sRGB gamut. What choosing an sRGB profile will do is lie to the OS about the color gamut of the monitor, saying that the display is sRGB when it isn’t. That lie will cause colors to display incorrectly.

But it isn’t Adobe RGB! Or does that matter?

Some creative professionals who don’t work in video may be concerned that Apple has gone with a P3 panel instead of an Adobe RGB (1998) panel. After all, Adobe RGB is the de facto standard for a wide gamut color space. When there’s a color space option other than sRGB in a photography or graphic design application or on a digital still camera, Adobe RGB is usually the alternative you get. For that reason, Adobe RGB is the gamut around which most wide gamut displays are built, such as those made by Eizo, NEC, and Dell.

By specifying a P3 gamut panel for the Retina iMac, Apple has consciously gone in a different direction. But you shouldn’t automatically conclude that P3 is going to ruin Adobe RGB workflows, because P3 and Adobe RGB are mostly the same size and shape. With P3 you do lose a few blues and greens, but you gain some yellows and reds. If color management is set up properly on your system, it will compensate for whatever color space your display uses and you should see consistent color. The only way P3 might be harder to use compared to Adobe RGB is if your work often involves the relatively few colors within Adobe RGB that are not within P3.

I did see one possible area of concern when comparing some CMYK/print color gamuts against Adobe RGB and P3. Some of the print blues and greens that Adobe RGB can cover look like they aren’t covered by P3. If print is an important output for you, you might want to compare the gamut of your typical printing conditions against P3 to find out if you would rather have an Adobe RGB display. But you’ll still see more CMYK colors with a P3 display than you would have with an sRGB display.

Adobe RGB, sRGB, SWOP CMYK, and iMac P3 gamuts compared

Adobe RGB, iMac P3, sRGB and SWOP CMYK color gamut comparison, based on plots by Color Sync Utility.

Note that the gamut plots I’ve shown are generalizations. For one thing, the size and shape of each gamut varies with luminance, so for example the P3 gamut is going to look a lot different when you dim it down to the DCI luminance spec for a digital projector. If you’re after the best possible visualization of gamuts, rotate them in 3D to see how they behave from light to dark. ColorSync Utility can rotate its 3D gamut plots, or you can use a more advanced gamut analysis tool such as Chromix ColorThink Pro which can also include sample images as part of the analysis.

The P3 iMac: color management required

I welcome any corrections to this article from color professionals who may have more hard data about how the P3 display works on the Late 2015 Retina iMac, and whether OS X was adjusted in any way to better handle wide gamut displays. Especially because my time with the new iMac was limited. But until I hear otherwise, here’s my take on it.

The wide gamut display of the Late 2015 Retina iMac should give you the best color you’ve seen on an Apple display, as long as you work in color-managed applications with content tagged with embedded color profiles. But untagged objects and colors in non-color-managed applications may display with distorted colors when rendered on a wide gamut display like this one. Because the Late 2015 Retina iMac display doesn’t seem to have an sRGB mode, if you need to proof colors for sRGB output, such as graphics in a game or app, or on a web page in a browser other than Safari, you may want to connect an inexpensive sRGB-calibrated display to the iMac.

If you’re creating work that targets larger color gamuts than sRGB, such as fine art printing or digital cinema mastering, the wide gamut P3 display of the Late 2015 Retina iMac looks like a real improvement over previous iMacs, especially if you’re working in a color-managed environment.

If you’re currently using a conventional sRGB-based display, the important difference is that P3 is still a big step up from sRGB, about the same as going from sRGB to Adobe RGB. You win about as much as you would have if the iMac had an Adobe RGB panel.

I’ve read about photographers who bought a wide gamut display and plugged it into the iMac because the built-in displays on the older iMacs didn’t completely meet their needs. Now that the current Retina iMac includes a wide gamut display, most iMac-using photographers no longer need to buy and plug in a separate wide gamut monitor and give up the desk space for it. For those photographers, the new P3 display of the Late 2015 Retina iMac should save them several hundred dollars and free up a few square feet of desk space.

(There is one more thing: While examining the color profiles on the iMac, I noticed several profiles I’d never seen in OS X before. Those new profiles have one thing in common, and I talk about that in the next article: New OS X Color Profiles Strengthen Mac Digital Cinema Support.)

Photoshop CS6 workspace

Can you buy Adobe software without a subscription?

There’s no question that Adobe Creative Cloud has been successful for Adobe. For the fourth quarter of 2015, Adobe reported record revenue partially driven by Creative Cloud subscription rates that exceeded their projections. Adobe seems to have found a combination of products, services, and subscription pricing that works for the customers they want, but a subscription model doesn’t meet every customer’s needs. If you want Adobe software but you don’t want to pay a regular subscription fee, what options do you have?

I’ll concentrate on Adobe software that’s used by creatives: Photoshop, Lightroom, and Acrobat, even though there may be other Adobe applications that are also still available without a subscription.

Just to get some terms out of the way, the conventional way to obtain software is called a perpetual license, because you buy the license once and it doesn’t expire. With Adobe Creative Cloud you maintain your license to use Adobe software and services by paying a subscription fee every year or every month, as you might with Netflix or Spotify.


The king of Adobe software is, of course, Adobe Photoshop. Editing images is such a basic need that many studios owned a copy of Photoshop even if they didn’t use it every day. Adobe still sells a non-subscription version of Photoshop CS6. You can get Photoshop CS6 only from Adobe, and only as a download. Discs are no longer available.

As of the date of this article, the following web page is the only remaining way to buy a perpetual license of Photoshop CS6 (at least in the USA):


Adobe web page for ordering Photoshop CS6

The page says:

Yes, you can still buy CS6 products by calling an Adobe call center, but why would you? The features in Creative Cloud will take your creativity further, with more ways to create, collaborate, and share. To purchase by phone, call 800-585-0774.

It’s no surprise that the page is written to try and nudge you to a Creative Cloud subscription. As more time goes by it becomes less practical to stick with Photoshop CS6, which was released in 2012 and is no longer being updated. To see if you’ll miss any of the features in the six Photoshop upgrades since CS6, check the Photoshop version history on Wikipedia. But updates also include fixes. While Photoshop CS6 still runs on current operating systems, there may be some problems with newer hardware such as HiDPI displays in Windows.

The current version is Photoshop CC 2015, and it’s only available through a Creative Cloud subscription. The most affordable subscription is the $9.99 Photography Plan which includes Adobe Lightroom CC; if you use Photoshop for business reasons this is probably going to be one of the smallest business expenses you have. The relatively low cost of the Photography Plan means that most of the people who don’t want to subscribe to Creative Cloud are opposed to it on reasons that aren’t economic.

After the launch of Creative Cloud, Adobe originally stated that Photoshop CS6 would remain on sale “indefinitely.” Through most of 2015 Adobe provided a web link where you could still pay once to buy a perpetual license of Photoshop CS6. But in late 2015, Adobe redirected the link to the current web page, linked above, that does not let you simply buy Photoshop CS6 online, only over the phone. So while Adobe still sells Photoshop CS6, they have decided to make you work for it.

Adobe Camera Raw and Photoshop CS6

Adobe Camera Raw lets you open and edit images that are in a camera’s raw format, and then send them on to Photoshop. Even after Adobe stopped updating Photoshop CS6, Adobe continued to let Photoshop CS6 use free updates of Adobe Camera Raw. Photoshop CS6 was able to take advantage of updated Adobe Camera Raw support for new camera raw formats, but not new Camera Raw features. Adobe Camera Raw support of Photoshop CS6 continued well into 2015, but Camera Raw 9.1.1 was the last version that works with Photoshop CS6. Newer versions of Camera Raw work only with Photoshop CC and later.

How do you know if your camera works with Camera Raw 9.1.1? Check the Adobe tech note Cameras supported by Camera Raw.

If your camera is new enough that Camera Raw 9.1.1 can’t open its raw image files, there is a workaround. Camera Raw 9.1.1 reads Adobe DNG raw files, so if you convert those images from their native camera raw format to the Adobe DNG raw format Camera Raw 9.1.1 can open and edit them. You can convert them using the free Adobe DNG Converter. This method bridges the gap because Adobe has continued to update Adobe DNG Converter for new cameras.


Adobe sells a subscription version and a perpetual license version of Adobe Photoshop Lightroom:

  • Lightroom CC comes with an Adobe Creative Cloud subscription. Lightroom CC has Creative Cloud-specific features such as the ability to sync with Lightroom Mobile, and it receives bug fixes and new features as they become available.
  • Lightroom 6 is sold as a perpetual license. In terms of features the main difference is that it doesn’t connect or sync to any Creative Cloud services such as Lightroom Mobile. Lightroom 6 receives bug fixes as they become available, but new features do not appear until the next major number upgrade. New features added after the release of Lightroom CC 2015 are not in Lightroom 6, and Adobe has not announced when the perpetual license version of Lightroom will receive a major upgrade.

Based on the number of people asking where you can buy Lightroom 6 (the non-subscription version), many don’t seem to be aware that you can buy Lightroom 6 at the same retailers where they buy other perpetual license software. For example, you can buy Lightroom 6 for a one-time non-subscription purchase at Amazon.com, B&H, and Adorama. However, those are for new full-price licenses; if you want a discounted upgrade from earlier versions of Lightroom you may have to do it through Adobe.com.

B&H Photo web page for buying Lightroom 6

There is an often-repeated rumor that Lightroom 6 is the last perpetual license version of Lightroom, but Adobe has never announced this and there is no proof of it. The rumor probably originated from misunderstanding an Adobe statement about feature updates not being available to Lightroom 6 specifically, not Lightroom in general. The Adobe statement was in response to users who didn’t understand that Lightroom 6 does not receive feature updates when Lightroom CC does.

Acrobat Pro DC

Acrobat Pro DC is what used to be called Acrobat Pro. The DC stands for Document Cloud. (If you still think that Adobe is mostly about Photoshop, and that the Creative Cloud is a mere side effort, the reality is the opposite. The currently successful Adobe business model is built around its three Clouds: Creative Cloud for creatives, Document Cloud for businesses, and Marketing Cloud for online marketers.)

While Adobe has made most Creative Cloud applications available only by subscription, and has made some of the remaining perpetual license versions difficult to find and buy, Acrobat Pro DC is an exception. Adobe still lists the perpetual license version of Acrobat for sale right next to the subscription version. There must be something about the Acrobat user base that motivates Adobe to keep the perpetual license highly visible at Adobe.com.

Adobe.com webpage for ordering Acrobat Pro DC

The Elements line

Years ago, hobbyists and non-professionals used to buy the full version of Photoshop because it was one of the few applications that could do a good job of editing images. Today many of those users may be satisfied with recent versions of Photoshop Elements. It’s sold from many retailers as a perpetual license for under $100, no subscription needed or available.

Over time many advanced features in recent versions of Photoshop (such as healing, hair selection, camera shake reduction, and panorama merge) have been handed down to Photoshop Elements, so some areas of Photoshop Elements are more powerful than older versions of Photoshop.

For video editing, Premiere Elements serves a similar consumer audience, and is also sold as perpetual license software.

Alternatives outside Adobe

Photo editing software has matured greatly since the days when Photoshop was the clear standout. On the Mac, hobbyists and others needing something more advanced than Apple Photos can turn to Acorn, Pixelmator, and others. However, photo editors at that level tend to be missing features that advanced and professional users rely on in Photoshop. If you do need more advanced features such as support for non-RGB color modes (such as CMYK and Lab) and ICC profile conversions, take a look at Affinity Photo. That affordable application seems much closer to Photoshop than most other alternatives. GIMP is also a frequently mentioned Photoshop alternative; it’s mature and powerful but can be challenging to learn.

Affinity is the developer to watch here. Before Affinity Photo they released Affinity Designer, a legitimate alternative to Adobe Illustrator. And Affinity is working on an alternative to Adobe InDesign. If that happens, Affinity will have a trio of perpetual license applications that covers much of the same ground as the old Adobe Creative Suite. Serif (the parent company of Affinity) certainly has the background to build it, as they are the developer of the long-established PhotoPlus, DrawPlus, and PagePlus applications for Windows.

Alternatives to Lightroom include Capture One, Darktable, Lightzone, and RawTherapee. If you value the organizational features in Lightroom you should evaluate the alternatives carefully, because in general their photo organization features are not as strong as their raw development features.

The big picture

Remember that Adobe Creative Cloud isn’t just about subscriptions. It includes features that perpetual license software usually doesn’t offer such as online services, online storage and portfolios, and connectivity with mobile companion apps. These benefits tend to have the most appeal for highly mobile creatives who work daily with the latest workflows and need features that support them. For example, if you frequently prepare graphics for websites that are Retina/HiDPI enabled, you’d probably want the Adobe Generator, Export As, and Artboards features that are in Photoshop CC 2015 but not in Photoshop CS6.

If you have a more modest or occasional workflow, like weekly processing of a few images for prints or an online newsletter, one of the non-subscription alternatives in this article might be all you need.

30-bit display color is now supported by OS X and Photoshop

For many years, Photoshop users and other graphics professionals have wanted proper support for 10-bits-per-channel video displays (also known as 30-bit when counting the three RGB channels together) on Macs. This isn’t about the file format, but the data path to the video monitor. The 8 bits per channel displays almost all of us use today may show banding when displaying gradients, especially in grayscale images, shadows, and in colors dominated by a single channel. That banding goes away on 10bpc displays because of the additional display levels available to each channel.

While 10bpc-capable displays, graphics cards, cables, and software (such as Photoshop) have been ready for some time, OS X itself has been the last missing piece everybody has been waiting for. Some developers earlier found clues in El Capitan that seemed to indicate 10-bpc display support, and now some users are finding that OS X is reporting 10 bits per channel from some Retina iMacs and Mac Pros, as in the following tweet is from Juergen Specht.

It’s difficult to find detailed information about 30-bit color in OS X, such as the requirements to make it work. Apple doesn’t seem to have published anything about it.

Also, without mentioning it in their release notes, Adobe added a new “30 Bit Display” option in the Photoshop CC 2015.1 that came out on November 30, 2015. Photoshop users found the new option themselves and started talking about it online. You’ll find it in the Preferences dialog box; click the Performance tab and then click the Advanced Settings button, as seen in the next figure. This screen shot is from a 2011 15″ MacBook Pro with discrete GPU and the built-in display only; this surprised me because up until now I heard you had to have a very recent Mac to use 30-bit color. But there it is (click image to enlarge). I just turned it on, so I still need to see if it makes any difference in gradients on the MacBook Pro screen or my NEC PA272. I don’t expect it to make much difference on the old MacBook Pro screen.

Two sets of full screen controls in Lightroom

Lloyd Chambers at Mac Performance Guide claims to have spoken with a contact at Adobe who said “Apple supports 30-bit output on iMac 5K under 10.11, while other devices get dithering with that option checked.” That raises the question of what OS X 30-bit color really does, especially with different combinations of graphics cards and displays. I wouldn’t expect my old MacBook Pro screen to do any better than dithered 30-bit.

Windows has technically supported 30-bit display color for some time, so I believe it was already possible to see the 30 Bit Display option in Windows. But I’ve been told that there are a number of technical constraints to get 30-bit color in Windows and so it isn’t necessarily enabled on a given Windows system or application (and usually, it probably isn’t enabled). Again, it’s hard to tell when it works and what it actually does.

I am not yet sure if Lightroom or Adobe Camera Raw support 30-bit color, though it is potentially just as useful in that software as it is in Photoshop.

Prints on display from Il Palio di Siena at Art Walk

Promotional image for Conrad Chavez photos at November 2015 Greenwood-Phinney Art Walk

Event: November 13, 2015 in Seattle

I’m showing a set of photographs from my from my series about Il Palio di Siena, including two large images I haven’t printed before. Il Palio is the centuries-old traditional horse race held twice each summer in Siena, Italy. Attending Il Palio was fascinating to me not because of horse racing specifically, but because of the colorful cultural and historical traditions that drive it.

The event is on November 13, 2015 from 6 to 9 p.m. as part of the monthly Greenwood-Phinney Art Walk. Join me at Nutty Squirrel Gelato, 7212 Greenwood Ave N in Seattle. (See location on Google Maps).

I ate a lot of gelato while attending Il Palio, so I am grateful to Nutty Squirrel Gelato for hosting my Italian photographs in an appropriate venue. In addition to the delicious treats available at Nutty Squirrel, there will be Art Walk-only art discounts and affordable gifts. I will also have additional prints and images that are not already on the walls. Hope to see you there!

More info: List of all participating venues and artists / Map of venues (PDF, 2-up)

If you can’t make it to the event, the photographs are on display throughout November 2015. You can also visit my Palio di Siena project website to see an extended photo essay and video of the works that I continue to create from this ongoing project.

Also, by a complete coincidence, SIFF (Seattle International Film Festival) is screening a documentary about Il Palio on November 14, 2015, the day after this event, as part of their Cinema Italian Style series. I haven’t seen it, but the trailer looks promising. For more information and a preview, see: Palio

Curious about Astropad? I reviewed it for CreativePro.com

Walk into a graphic design or photography studio and you’ll probably see a graphics tablet on the desk. With an app called Astropad you can use an iPad or iPhone as a graphics tablet for a Mac, painting and drawing with your finger or stylus. Astropad even supports pressure sensitivity with a compatible stylus or with 3D Touch on the iPhone 6s and 6s Plus. But how close does it get to using a Wacom graphics tablet?

To see what I think, read Review: Astropad, published on CreativePro.com.

Astropad review on CreativePro.com

New OS X color profiles strengthen Mac digital cinema support

For creative professionals, one of the most interesting things about the Late 2015 release of the 4K and 5K Retina iMac is that it uses the first wide gamut display Apple has ever made. And the color gamut it uses is not the Adobe RGB gamut usually seen on wide gamut monitors, but a gamut called P3 which is used in digital cinema.

Mac websites have not gone into much detail about this display except to more or less repeat what Apple says in their marketing materials, so I took a closer look at this display in my earlier article, A look at the P3 color gamut of the iMac display (Retina, Late 2015). As I was examining the wide gamut P3 display, I realized that there are several color profiles installed with OS X that I haven’t seen before. What led me to write this article was that almost no one seems to have mentioned these new profiles…and what they have in common.

New color profiles installed with OS X 10.11 El Capitan

While looking through the profiles included with OS X El Capitan on the Late 2015 Retina iMac, I noticed several profiles that were not installed with earlier versions of OS X:

  • ACES CG Linear (Academy Color Encoding System AP1)
  • Display P3
  • Rec. ITU-R BT.2020-1
  • Rec. ITU-R BT.709-5
  • ROMM RGB: ISO 22028-2:2013
  • SMPTE RP 431-2-2007 DCI (P3)

When I got back to my own old Mac, I confirmed that none of these profiles is included with OS X 10.10 Yosemite, but all of them are included with OS X 10.11 El Capitan. So not only are they new in El Capitan, but you get them even if you don’t have the new iMac, since I also found them in the El Capitan installation on my 2011 MacBook Pro.

Default system profiles in OS X 10.11 El Capitan

Default system profiles in OS X 10.11 El Capitan as seen in Apple ColorSync Utility, with new profiles highlighted in yellow

Profiles for a specific industry

What struck me about these new profiles is that they’re related to one specific medium, and it’s the same medium that’s most concerned with the P3 color gamut: professional digital cinema. Let’s walk through the list.

ACES (Academy Color Encoding System) is a new workflow system specification by the Academy of Motion Picture Arts and Sciences; in other words, Hollywood (as in “Academy Awards.”) Digital production of major motion pictures involves a complex web of hardware, software, and people that changes over time. ACES was designed for archiving, editing flexibility, interoperability, and device independence, helping to standardize that complex workflow and overcome incompatibilities. The ACES CG Linear color space is part of the overall ACES workflow, using a very large gamut so that it can accommodate all input and output color spaces for digital and analog video and film.

P3 is a color space based on the gamut of the high-end digital cinema projectors used in movie theaters. In other words, the P3 color space represents a typical final output device for digital cinema.

The two profiles that start with Rec represent color gamuts used in the video standards known as Rec. 2020 and Rec. 709. Rec. 709 is a current standard that’s almost identical to sRGB, while Rec. 2020 is a proposed standard that uses a much larger color gamut to accommodate upcoming display technologies.

The SMPTE profile that ends in P3 appears to be another P3 profile; I am not completely clear on how it might be different than the Display P3 profile except that its gamut is a little smaller. Some brief research indicates that there are several variants of P3 due to different white point specifications. The entire profile name is important (SMPTE RP 431-2-2007 DCI (P3)), because there is another standard with “2011” in its name instead of “2007”. If the 2011 version is some kind of update, I don’t know why OS X includes the 2007 version unless it’s a more widely used standard.

If you’ve ever come across a profile named SMPTE-C, that’s a completely separate older profile that’s probably on your system because of an Adobe installer. The reason all of these profile names all start with SMPTE is that they’re standards defined by the Society of Motion Picture & Television Engineers (SMPTE).

The ROMM RGB profile seems to be the odd one. ROMM RGB is another name for the ProPhoto RGB color space, which I thought was used more by photographers than video editors.

Because I don’t work in high-end video, my descriptions of those profiles may be a little off. If so, feel free to correct me in the comments. I was able to recognize the new profiles as video related thanks to the online show Home Theater Geeks, which frequently covers emerging developments in color and display technologies that are driven by digital cinema and are often not noticed by photographers and designers.

If you’re wondering how the gamuts of these new profiles compare in size and shape, here’s a chart based on the 3D gamut plots from Apple ColorSync Utility.

2D plots comparing the gamuts of the new color profiles in OS X 10.11 El Capitan

How would you use these new profiles?

Several of the new profiles are not intended to be display profiles, because for example you simply can’t buy a display that covers the entire ACES CG Linear or Rec. 2020 color spaces. The very large gamut profiles serve a function similar to the role of the ProPhoto RGB color space in still photography: They cover a wide theoretical color space so that full range cinema masters from diverse sources can be edited while preserving as much of their original color quality as possible. You then preview edits on a display that supports one of the reference output standards, such as Rec. 709 or P3. If you’re using a professional video application such as Final Cut Pro X or Adobe Premiere Pro, having these profiles in OS X should make them available as color space options when you export video. These profiles should also allow soft-proofing (simulating how color will look under specific output conditions) in applications that support it.

Some of the new profiles can be useful as display profiles when you are certain that a monitor has been hardware-calibrated to a specific video standard, as is often found in video production. For example, if your Mac is connected to a video preview monitor that’s precisely hardware-calibrated to Rec. 709, you can assign the Rec. ITU-R BT.709-5 profile to it using the Displays system preference panel in OS X 10.11 or later.

Is Apple defining itself as the digital cinema platform?

Because the new profiles are primarily associated with digital cinema, I get the impression that Apple is using digital cinema to differentiate its platform as they did when they shipped Macs that integrated the DV and FireWire standards of the late 1990s and marketed them as digital video editing solutions. The most powerful technologies used in Macs today — Thunderbolt 2, built-in superfast PCI flash mass storage, P3 wide gamut 4K and 5K displays — provide capabilities that most users don’t need for general computer usage. But all of those technologies are required to support the resolution, color, and bandwidth demands of the Ultra HD/wide gamut professional digital cinema workflows and standards that are already in use or on the way. If you are editing video for P3 4K digital cinema projectors, you aren’t going to see all your colors and pixels with an sRGB-based standard resolution monitor, but you will with the latest Retina iMac. Or with another Mac driving a wide gamut 4K display. I think the new color profiles in OS X 10.11 El Capitan are intended to be combined with the above technologies to give the Mac platform broad and robust support for the emerging standards of professional digital cinema.