Versione in Italiano QUI
Introduction
Over the course of recent years, there has been a growing number of monitors designed to cover the Display P3 color space as accurately as possible, which some are already beginning to refer to as “the new standard.”
Because “standard” doesn’t always translate to “what is technically and universally superior,” and after observing a bit of confusion surrounding the implementation of this color space in the world of photographic printing, here I am with a new lengthy and potentially tedious article!
Preliminary Note
As always, I’ll be making a lot of simplifications to make the reading as enjoyable as possible. However, in order to fully grasp the various considerations, a basic understanding of the world of color management is required. If you’re unsure where to start, you can find some of my videos on this topic on YouTube, and for those who are interested, there’s always the option to explore the subject further through individual lessons HERE.
The first, and hopefully obvious, simplification is that when we refer to “photographic printing,” we’re talking about home photographic printing using pigment or dye-based printers, or printing done through online printing services.
What are P3 Color Spaces?
As you are well aware, standard color spaces are not found in nature like apples, apricots, or uranium. They are created (or rather, designed) by humans to address specific needs.
We already know that sRGB was developed to establish a standard suitable for the typical display requirements of home and office environments (back in the 90s…), while our beloved Adobe RGB was designed to encompass many of the colors achievable with CMYK color printers, but using the RGB primary colors on a device like a computer display.
P3 color spaces emerge from a different need. To simplify greatly, around 2002, the American film industry faced the “problem” of the emergence of digital cinema projectors in movie theaters. These projectors were capable of smoothly projecting images onto a screen, but the issue was that a consistent result couldn’t be achieved from one projector to another. Furthermore, the viewing experience for the audience was starkly distinct from that of projecting film.
Given that Hollywood never seems to run short of budget, it’s not difficult to imagine that, much like what Microsoft and HP did back in 1996 for sRGB, the Digital Cinema Initiatives consortium sat down to find a solution. This eventually led to the design of the DCI-P3 color space (DCI being an acronym for…). This color space has a volume not much different from Adobe RGB, but with a monochromatic R primary, a white point at 6300K, and a gamma of 2.6. To an observant printer, this might raise an eyebrow, and indeed, we don’t even consider using DCI-P3 for printing.
But the story doesn’t end there, of course. Since this color space became the cinematic standard, someone eventually asked a new question that went something like: “How do we ensure that these beautiful movies we watch in theaters can also be comfortably viewed on our laptops while lying in bed, with a viewing experience not too far from that of the cinema, taking into account the technology of today’s computers?”
This is how, thanks in large part to Apple along with Netflix, YouTube, and other video content providers, the Display P3 color space came into being. It’s closely related to our DCI-P3 but fundamentally characterized by a different white point (D65) and a gamma of 2.2 (values that no longer make us raise our eyebrows like before).
If we look at the image below, comparing the volume of the sRGB color space (in red) with that of Display P3 (rainbow), it’s not hard to imagine why the collective dream is for Display P3 to replace sRBG as the standard for online display, and why even manufacturers of photographic monitors, who were traditionally focused only on Adobe RGB, are now seeking to cover Display P3 as well.
But do the same considerations apply to printing?
Display P3 vs Adobe RGB
At this point, it’s reasonable to wonder if Display P3 could potentially replace our beloved Adobe RGB, as I increasingly read online.
To explore this, as always, let’s start with our CIE chromaticity diagram, where we can compare our two color spaces. From a basic two-dimensional analysis, we can first observe that the two color spaces seem to have fairly similar coverage: Display P3 covers about 45% of the CIE chromaticity diagram, while Adobe RGB covers around 52%.
What stands out, however, is their different positioning on the diagram (or, more precisely, the positioning of their three primaries on the diagram): we can see that the green primary of Adobe RGB is closer to the ideal primary (and somewhat bluish, with a wavelength of 534.7 nm), while Display P3 has a red primary that’s closer to the ideal primary.
If we wanted to delve into the depths of nerdiness, from a similar three-dimensional analysis, we would see confirmation overall, with only a few nuanced differences in luminance. I’ll provide you with images from various angles for comparison (hoping that something can be understood, given that it’s not very straightforward with static images).
At this point, the most obvious question might be: which one is better?
As seasoned photographers, though, you wouldn’t express yourself dogmatically when it comes to screen visualization: volumetrically, these spaces are quite equivalent, so the “total number of available colors” (in quotes because I’m simplifying mercilessly) is roughly the same. The real difference is that Adobe RGB gives me a bit more greens and blues, so if I were a forest or seascape photographer, it would benefit me if my monitor’s gamut covers that part of the color space. On the other hand, if I were a photographer of sunrises and sunsets, I’d be advantaged by Display P3, which offers more colors in that region. If I do both (like most landscape photographers, for instance), there’s no absolute better choice.
In reality, the only hope we have for screen display is that an external factor finally displaces sRGB as the standard for online viewing (remember, sRGB is a truly limited color space that we’ve been dragging along for almost 30 years!). It seems that Display P3 is on track to do just that, driven certainly not by the interests of photographers, but by the commercial interests of the video world. However, at the time this article is being written, we remain bound to sRGB whenever we want to publish our images online.
And what about printing?
Display P3 and Photographic Printing
Here, the situation changes significantly, and not just a little.
So far, we’ve looked to Display P3 as a savior, which, at the cost of some greens and blues compared to Adobe RGB, promises us a drastically larger gamut (and thus “more colors”) than the typical sRGB. But this is essentially a side effect – something that is convenient for us, even though it wasn’t intended for our use, and it suits our purposes due to the limitations of sRGB.
However, I return once again to a fundamental point: color spaces are designed to serve a purpose, and as we’ve seen, the purpose of Display P3 isn’t printing, whereas it is for Adobe RGB.
To convince you, I believe this two-dimensional analysis should suffice:
As you can see from the image above, the Adobe RGB color space is positioned to almost entirely overlap the gamut of the paper. The paper used here is one of the numerous types of photographic papers available (simply because it’s the one I use most often), but the same would hold true for any other paper: the paper’s gamut could be smaller or larger, but Adobe RGB would still intersect with it. And that’s where Adobe RGB fits.
Once again, Adobe RGB wasn’t designed arbitrarily; it was created to encompass many of the colors achievable with CMYK color printers (the home photo printers or online printing services you use) through the use of RGB primary colors (i.e., the color model your monitor uses). In other words (and simplifying significantly), Adobe RGB was designed based on what our printer can reproduce on a sheet of photographic paper.
Sending an image in Display P3 to print means sacrificing a significant portion of printable colors (greens and blues) in favor of more reds, which our printer is not capable of reproducing. The Display P3 color space is situated elsewhere on the CIE chromaticity diagram because it was designed for a different purpose.
A practical example can be provided with the following image. If we were to analyze its breakdown on the chromaticity diagram, we would notice intense blues that wouldn’t be problematic, as they are within the paper’s gamut and manageable in Adobe RGB. However, if we were to associate this image with the Display P3 profile, those blues would be lost because they would fall outside the gamut of Display P3. It’s an unnecessary sacrifice that brings no advantage.
It’s clear, however, that the above considerations depend on the specific image we are using. For instance, its breakdown might fall within a region of the chromaticity diagram covered by both Display P3 and Adobe RGB, so we wouldn’t actually lose anything in that case. Similarly, the certainty remains that some colors within Display P3 are not printable with our printer. Therefore, unless you perform this analytical assessment of your images every time, it doesn’t really make sense to risk losing colors by using Display P3 for printing.
Conclusions
We might be nearing the day when sRGB will be surpassed as the visualization standard in favor of a much richer color space like Display P3. Though not designed for photographers, luck has it that it possesses characteristics that make it, if not ideal, at least a significant leap forward that we welcome with open arms.
However, for the world of printing, the situation is different because we already have a color space purposefully designed for the task, which is Adobe RGB. Display P3 shares a similar gamut volume and positioning, so in itself, it wouldn’t bring improvements but rather new compromises linked precisely to its position (“more reds in exchange for greens and blues”). Despite this, even if it were a much broader profile, Display P3 clashes with reality since it doesn’t account for the characteristics and physical limitations of printers, as it’s not designed to convert RGB triplets to CMYK, the color model our printers operate with.
Technological innovation knows no bounds, so one day we might have new printers and papers capable of achieving previously unimaginable gamuts, rendering Adobe RGB inadequate. However, if that were the case, I don’t believe Display P3 would be the solution.
For this reason, my suggestion is to continue working for print using Adobe RGB, which has been specifically designed for that purpose. On the other hand, if you’re about to replace your monitor (be it an external one or on a laptop), I would recommend seeking something geared towards the likely future of visualization and therefore with the highest possible coverage of the Display P3 color space.