What is the difference between RGB and CMYK files.

What is the difference between RGB and CMYK files and why should I care?

RGB and CMYK are two different color spaces used in digital and print media. The main difference between them is the color range (gamut) of each. We will first talk about the two color gamut’s and their differences, and then how to boost the existing colors and vividness of an image when using ProRip.

The above picture shows the color gamut (Range) of CMYK VS RGB. The LAB section shows what our eyes can see.

1. RGB (Red, Green, Blue):

RGB is an additive color model used mainly for electronic displays, such as computer monitors, TVs, and digital devices. It works by emitting light in different combinations of red, green, and blue to create a wide range of colors. In RGB, the absence of color produces black, and the maximum intensity of all three colors produces white. This color space is based on the concept that when the three primary colors are combined at their highest intensity, they create pure white light.

RGB color space is ideal for digital media because it covers a wider gamut of colors and is used for capturing, displaying, and editing images and videos on screens. Pretty much all website images are and should be RGB.

2. CMYK (Cyan, Magenta, Yellow, Black):

CMYK is a subtractive color model used in print media, including books, magazines, brochures, and newspapers. It works by subtracting varying amounts of cyan, magenta, yellow, and black inks from a white background to produce different colors. The more ink is added, the darker the color becomes. In CMYK, the absence of color produces white, and the maximum intensity of all four colors produces black.

CMYK is used in printing because it replicates the way pigments and inks interact with each other on paper. Printers use these four ink colors (Cyan, Magenta, Yellow, and Black) to reproduce a wide range of colors, and the black ink (K) is added to improve contrast and produce richer blacks.

3. Why should I care?

The biggest consideration when designing an image is that RGB has a wider gamut than CMYK. This means that some colors that can be displayed on a screen may not be accurately reproduced in print, as the CMYK color space has a more limited range of colors. So, when preparing graphics for print, it's necessary to convert them from RGB to CMYK to ensure a more accurate representation of the final printed colors. Better yet, design them from the start in CMYK

You can see from the above picture that the RBG color space has much brighter colors available than CMYK. Most software will convert RGB files to CMYK when printing and will do a decent job but if the colors are too far outside the CMYK range the result may not be what you’re looking for.

Once your file is saved/created correctly, it is possible to boost the colors when using ProRip software.

4. Adjusting colors in ProRip

With an image open in ProRip, click on the Job tab and then Color Adjust

With the Color Adjust window open you can see where you can boost or lower each of the CMYK colors separately by moving each slider or inputting a specific #.

Below the CMYK Adjustments are the Brightness and Saturation sliders. These are both typically adjusted, not just one alone. When boosting the Saturation, you want to lower the Brightness. You can change them to be any number, but I have found it best to keep them close to the same # for a better balance. So if boosting the Saturation to 5 you would lower the brightness to someplace close to -5

Lastly you can also change the amount of white used to cover the image. It’s normally not necessary to change but if you want to, click on the Processing Options tab under Color Adjust.

5. ICC color profiles

All the ICC color profiles are built into ProRip. When you choose your print media and ink being used from the dropdown. As shown below, you are also choosing the built-in ICC Color profile for that film and ink. It’s very important that you match the ink and film in the dropdown to what is actually being used for best color reproduction. You also choose the DPI of the printed image here.

So while the best format to use is CMYK, there are times when an RGB file is necessary. As long as the colors in the RGB file are within the CMYK gamut, you should be fine. You can then boost the colors in ProRip as shown above.