Join Joe Brady for an in-depth discussion in this video Understanding color spaces, part of Learning Color Management.
As a basis for everything we're going to put into use through this course, let's introduce some basic concepts that will make understanding the world of digital color a bit easier. We're going to start with color spaces. Color spaces define the range of colors and tones available for a digital file. You might think that the largest one will always be the best. So I'll just go with that one. Well, this is frequently not the case, so we're going to explore this. Color spaces are an area that cause a lot of confusion, so it's important to understand where they all fit in and what characteristics may affect how an image is viewed.
First of all, let's clarify one thing. There are no bad color spaces. While it is true that some spaces have a much greater color range, many devices that we use are impacted by color workflow, simply because they can't display or create all of the colors that larger color spaces have. For example, ProPhoto RGB is the largest common color space you'll encounter. Now, this sounds great because it can accurately represent practically all of the colored depth that the best digital cameras can capture. As wonderful as this sounds, most current monitors can only display sRGB, with professional level monitors expanding that to Adobe RGB.
What happens to those colors you can't see? This will become clear again later when we explore Rendering Intents. Now there are four primary workspaces or color spaces that a designer or photographer may encounter, with a fifth one still hanging on by a thread, and that's ColorMatch. I listed from larger to smaller color volume, here they are, ProPhoto RGB, Adobe RGB, sRGB, ColorMatch and CMYK. Now you may have noticed that I said color volume when listing these color spaces. As you'll see sRGB may have a greater volume of colors but both CMYK and ColorMatch have a slightly greater ability to represent blues and greens than sRGB.
Seeing the color spaces together is going to make it simple. I'm going to use an app on the Macintosh operating system called the ColorSync Utility. This allows me to show you different color spaces and profiles and how they relate to each other in three dimensions. Now this app doesn't actually play any part in putting our color work flow together. I'm just bringing it up because seeing the color spaces makes it easier to understand what's going on. So let's jump into that app. So here's the ColorSync Utility. And you can see, if we click on Profiles up at the top here, we get a list of all the profiles that are in our system.
So if we bring up, say, Adobe RGB, we then get a plot of it. And you can grab it and spin it around. Now that's all very lovely but it doesn't tell us a whole lot by itself. We need to compare it to something else. So let's leave that there. And if we click here and click on Hold For Comparison, we can overlay other profiles on top of this. So let's take a look at sRGB. So we click on sRGB and we get to see the sRGB space in color inside the grayed out Adobe RGB space.
So what this is showing us is that Adobe RGB is larger in every color dimension than sRGB is and you can see in particular the greens and blues on the one side, there's a lot of extra space over here. Now if we hold sRGB, again here we have it by itself. Let's take a look at it with say, CMYK. Now CMYK is a much smaller color space than sRGB. But as I mentioned, however, as we spin around, you can see that CMYK does have a lot of blue and green that sRGB just can't address.
That's a common reason that a lot of designers will work in Adobe RGB when they have an image that's going to go out to a CMYK printer. Because Adobe RGB completely encompasses CMYK. Let's take a look at that. So we hold CMYK, and let's bring in Adobe RGB. And you can see it's completely surrounded the CMYK profile. In fact, we can reverse this so you can see it again. And then put CMYK inside. You can see even though Adobe RGB is a much larger space, it still gets used because it completely encompasses CMYK.
There's a lot of talk about ProPhoto RGB. Let's bring that up by itself. We'll clear this comparison and bring up ProPhoto, and yes you can see we have this enormous color space. You would think, well that must be wonderful. I want to use that one, it's like having more crayons in your box. Well if we go ahead and hold this, we can put Adobe RGB in there. And you can see, wow, it's much bigger than Adobe RGB and it completely dwarfs sRGB and in CMYK you can imagine what that's going to look like. Tiny inside there.
So you would think again, Adobe RGB is good for CMYK but why don't I want to use ProPhoto RGB? Well, in some cases you will and we're going to get into this when we get into the software a bit more. What we need to understand is that there are no devices that can actually show us ProPhoto RGB. So if your image contains colors that are way out here, for example, your monitor can't show it to you and your printer can't print it. So there are some reasons to stay away from it and we'll get into that more in software, it'll make a lot more sense. This utility is handy to have just for demonstration purposes.
You don't really need to know it, I do use it sometimes, however. For example, if I want to see how a printer profile or a paper profile fits inside my color space. For example, here's Adobe RGB. I have this held and I can take a look at one of my favorite papers. Here's a ILFORD Gold Fiber Silk and I can see Gold Fiber Silk can print a lot more colors than Adobe RGB can handle. There is the reason that you might want to go ahead and use ProPhoto RGB. In that kind of workflow, when going out to a printer that can print on this paper, because this particular paper can handle a lot more color than Adobe or RGB can.
And what ends up happening is, if you work in Adobe RGB, and your image contains these colors that this paper can print, they're going to get moved, they're going to get clipped off or moved into a different color space. And that will become clearer when we get into the software and learn all about Rendering Intents.
- Understanding color spaces
- Understanding the color workflow for photography vs. design and web
- Setting up a digital camera for the best image results
- Choosing a monitor
- Calibrating a display using ColorMunki or i1Pro 2
- Choosing color settings in Photoshop
- Understanding color workflow in raw processing applications
- Creating a custom printer profile
- Soft-proofing images for printing on your own printer and for sending to a lab