In parts one, two, and three of this ongoing series, we went over the photographer’s version of the color theory, the science that necessitates that color theory, and the difference between RGB and CMYK. Here, in part four, we’ll go over choosing the correct photoshop color settings for your needs.
So, we already know that the RGB (Red, Green, and Blue) primaries are based on the cones in our eyes, each of which is sensitive to a different range of light wavelengths, which is how our brains detect color. What we didn’t talk about, however, is how this plays into the range of colors we can actually see. For obvious reasons, having cones that are sensitive to a wider range of wavelengths would allow you to see a wider range of colors. (Interestingly, there are people out there with a fourth cone who can see colors you and I can’t even imagine.) Below is a simple graph that shows the range of hues, or gamut, that the average human eye can see.
You may notice that a lot of the colors in that graph look basically the same, especially in the Cyan to Green range. That’s because, while your eye can see all the wavelengths represented on this graph, your computer screen can only show some of those colors. Since it’s missing many of the colors you can see, this graph just stretches out the Cyan-Green range of your screen’s gamut to the edges of the graph, resulting in a large area of mostly the same colors.
Unless you have a fancy, professional photography monitor, your screen can only display what is called the sRGB color space. A color space is basically what you see in the above graph, a range of colors that can be displayed. sRGB is the most popular color space out there, and it uses three simple primaries that are nowhere near the limit of human vision, but were easy to build into monitors made in the mid-90’s, when sRGB was invented. Below is a graph just like the one above, but only the colors that fall into the sRGB color space are shown, and the outlined area is all of potential human color vision.
Pretty lame, right? Look at all of those colors you just aren’t seeing when you view a photo on your computer screen. Luckily, there are ways to expand your photos’ color gamut, but they aren’t always your best bet.
Adobe RGB is a color space just like sRGB, but it offers a 35% larger range of colors. Almost every camera is capable of capturing photos in this larger color space, but you’ll need to find it within your camera’s settings menu. If you shoot in 16-bit RAW (which you usually should, also in your camera’s settings menu), then you won’t need to worry about this since all of your image processing can happen after the fact in Lightroom or Adobe Camera Raw. Pretty much any image, even JPGs, can gain some color pop by using the Adobe RGB color space, but this will result in some slight banding in JPGs, especially if the image is edited further. Remember that most computer screens can’t actually display the extra colors anyway, so it’s not always helpful to change to an Adobe RGB color space. But if you’re interested, here’s how to change your working color space in Photoshop to Abobe RGB.
Open the color setting menu, then change the RGB working space from sRGB to Adobe RGB (1998).
As you can see, there are a whole lot of working color spaces available. That’s because different hardware and software use different standards, but your safest bet for web and almost everything else is sRGB. In fact, using Adobe RGB for web actually makes your images look duller, since your browser will compress the extra colors back down to sRGB, usually with poor results. So unless you plan on printing your photos with a decent photo printer, you should probably stick with sRGB. If you know you will be using a professional printing service, you can even open your RAW files in ProPhoto RGB (but don’t do this with JPGs). The rest of the color spaces you can safely ignore, since they’re very specialized.
Below, you can see the relative color gamut of sRGB (small but best for web), Adobe RGB (larger but only useful for print or professional monitors), and ProPhoto RGB (very large but only good for RAW files that will be printed).
Now, you’ve probably noticed that the ProPhoto RGB triangle appears to extend out of the horseshoe of human vision. That’s because this color space can actually perceive and display colors you can’t even see. On the other hand, there’s still a big chunk of Cyan-Green missing from this color space, so it’s certainly far from perfect. Another interesting tidbit on the graph above is the inclusion of 2200 matte paper’s color gamut. You’ll notice that this particular paper (paired with a generic set of photography inks), can display some Oranges and Yellows that are only available in the ProPhoto RGB color space, some Cyans and Greens that are only available in the ProPhoto and Adobe RGB color spaces, and can’t display some Blues and Magentas that are available in even the smallest, sRGB color space. Herein lies the crux of the color space dilemma.
If you’re printing your images, which color space should you use? Your best bet is Adobe RGB since it will cover almost all the space of almost every type of printer/paper combo. If you’re really serious about getting every ounce of color possible, ProPhoto is the way to go. Just remember that no monitor can display all of the ProPhoto colors, so editing may take a bit of guess work. If you aren’t too concerned with getting the most color possible and want the easiest workflow you can have, with no conversion necessary between print and web, stick to good ol’ sRGB.
If you send your files to a professional printing service, they should be able to print from any of these spaces with any paper you choose and get good results. If you use a less serious, online service like Shutterfly, you’ll need to send them sRGB files, otherwise the conversion process could give you unsavory final prints. If you’re printing them yourself on your own printer, just follow the color profile setup instructions that come with the paper and you should be all set. Paper manufacturers know a lot more about how their paper handles color than you or I, so it’s best to just trust them.
In Part five of this series, we’ll take everything we’ve learned and put it towards actually improving as photographers. We’ll even go over some ways to hone in your color vision, allowing you to literally see colors that you’ve never seen before.