Do you ever wonder why your images look a bit different when you print them?
Then it’s time to learn about RGB vs. CMYK. You can use them to get accurate tones when you switch from your computer screen to paper.
Let’s see the differences between these two color models.
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Why Is Getting Familiar with CMYK vs. RGB Crucial?
Colors may be everywhere, but they manifest in different ways.
Some objects emit light, while others reflect them. Due to this difference, it only makes sense that colors also manifest differently on various materials. So don’t be surprised if a printed photo looks different from what you saw on your computer screen.
We use color models to explain the behaviour of light on different materials. The most common ones are RGB and CMYK.
RGB is a color model that defines how light-emitting objects such as light bulbs behave. The term is short for red, green, and blue. It’s an additive model, which means that when you combine light sources with these specific colors, you end up with white.
CMYK is a model that defines how different colors of paint or ink interact with each other. It stands for cyan, magenta, yellow and key (a.k.a. black). It’s a subtractive model, which means that when you combine ink with the tones we mentioned, you end up with black.
RGB and CMYK also appear as color profiles on our computers.
The goal of using color profiles is to ensure that tones remain accurate as we print our digital files. It’s crucial that what you see on the screen matches what you see on the paper.
Most photo editing software such as Photoshop has CMYK and RGB color profiles for digital and print work, respectively. You must know what medium you want to use to display your images. This way, you can use the best option to ensure accurate results.
If you look at a digital screen, you’ll find that it consists of red, green, and blue dots.
To display specific tones and hues, each dot varies its light output to achieve the color they need to create. To create white, RGB dots light up brightly on your screen. For black, they don’t light up at all.
To display other colors, your screen uses certain combinations of red, green, and blue. For instance, to create magenta, red and blue light up, but the green doesn’t.
All digital screens use RGB. But there’s a wide variety of display types, from AMOLEDs to LCDs that produce inconsistency in colors.
AMOLEDs are like tiny light bulbs that emit light. Meanwhile, LCDs don’t produce light by themselves. Consequently, they require a white backlight to display color.
Both systems have pros and cons. For instance, AMOLEDs create more vivid tones. But at the same time, LCDs are much more capable of displaying whites.
You can often find AMOLED technology on television and phone screens. Meanwhile, LCDs are more common in laptop displays and monitors.
In the image below, you can see a phone and a laptop displaying the same photo. The computer has an LCD screen, while the phone has an AMOLED screen. As you can see, they both show colors slightly differently.
To ensure your screens display accurate colors, you will need to calibrate them.
Buy a screen that has a 100 % sRGB coverage would also be of great help. In other words, it has to have the ability to display the entire spectrum of colors possible with RGB.
And, if you plan to print your work regularly, you need to get a high-gamut display, too. These are capable of displaying colors of images that will later go into print.
Read our article about the best monitors for photographers to learn more!
People often use CMYK for print material. Here, the ink colors cyan, magenta, yellow, and black (key) are used to create different colors.
If you look at your printer, you’ll see that it uses CYMK ink cartridges. Often, CMY is in one cartridge, and K (black) is in another one.
In some ways, CMYK works much like RGB. It also uses specific combinations of primary colors to create thousands of tones.
But since CMYK is used for prints, its process of creating colors is a bit different.
Theoretically, a combination of cyan, magenta, and yellow create black — just like a combination of RGB creates white. But, to save all that ink, it’s much better to use key (black), instead. And since CMYK is not capable of producing white, printers use the white on the paper to display that specific color.
Displaying colors using CMYK is also different from RGB. Instead of using dots, it often lays one layer of ink on top of another to produce various tones.
But to create other colors, the same concept that RGB uses applies. For instance, a combination of cyan and magenta produces blue. Meanwhile, yellow and cyan make green.
Just like RGB screens, various printing processes also vary in how they apply CMYK. Different options include offset printing to digital.
Photoshop sometimes includes CMYK profiles that apply to specific commercial printers. So, if you’re working with professional print labs, it would be best to ask the technicians what particular type of profile they use.
When Should You Use RGB or CMYK?
RGB is the default color profile for displaying digital images. So, if you don’t plan to print your files at all, there’s no reason to switch to other options at all.
However, you’ll need to use CMYK if you want to publish your work. If you don’t, you’ll end up with inaccurate colors.
How Do I Convert RGB to CMYK?
If you’re working with a digital image, then its color profile is most likely RGB by default.
To confirm that your file uses RGB, you can check it by going to Photoshop’s Image tab.
Once the dropdown menu appears, go to Mode, and look at the checked profile. That’s how you know if your image uses either RGB or CMYK.
You already know that RGB is perfect for displaying images on screens. But what should you do if you need to print your image?
If that’s the case, then you’ll need to convert it.
To convert your RGB file, go to Edit. Then click on Convert to Profile.
Now look for the Destination Space and click on that field.
As you can see, there are plenty of color profile options available for you.
In most cases, choosing Working CMYK U.S. Web Coated (SWOP) v2 is the best default option. It works with regular office and home printers.
As mentioned before, if you’re working with a professional print lab, it would be best to ask them what type of CMYK profile they use. That way, you can guarantee you get accurate colors.
Now, let’s check out the difference between RGB and CMYK.
Here’s an image using an RGB profile:
And here’s an image using a CMYK profile:
The color variation may be so subtle that you can barely see. But CMYK looks a bit duller than the RGB version. If you’re using your image for print, this is acceptable. But, if you intend to publish it online, the small changes could affect the overall quality of your image.
Check out our post about color management to learn more about color profiles (it includes the greyscale method for all the black and white photographers out there!).
If you intend to print a lot of your work, you must pay attention to RGB and CMYK profiles. This way, you don’t end up with crazy tones when you publish your photos in a magazine.
But, if you want to keep your work on your computer, there is no reason to convert your files to CMYK. RGB is the ideal profile for that purpose, and it’s the default setting for your images, anyway.
Even if you haven’t printed any of your work before, remember what you learned about CMYK and RGB. You never know when you’ll need it.
And your knowledge makes all the difference between a good print and a bad one.
For great tips on how to edit your photos so that they look stunning in print, check out our course Effortless Editing with Lightroom here.