RGB or CMYK for Photo Printing? – Know the difference

Have you ever printed your photos only to realise that they don’t appear the same on screen? Many of us do not know the type of color space produced by our digital cameras hence get confused when printing photos. In today’s PFF blog, we will explain the difference between RGB and CMYK colour mode that is involved in the photo printing process.

What is RGB?

RGB stands for the three physical primary colors RedGreen, and Blue. It is mainly used for digital domains e.g. this blog on your screen right now or photos taken with a digital camera or phone. Considered an additive colour model since it produces all colors when added to the black monitor. Usually, the more light that is added to the monitor, the more white is produced.

RGB is the standard colour mode throughout most applications is that it produces the widest selection of colours and with great accuracy. Most photo-editing programs use RGB as standard (including Photoshop) which is why you need to be mindful when designing for print or editing photos (more on this later).

The more color is used → the lighter the final image will be. When all three primary colors are set to, the perceived color will be “white”
Source: iPrintdifferent

What is CMYK?

CMYK works in an entirely different way to RGB as it uses subtractive colours: Cyan, Magenta, Yellow and Key (simply another name for black). This means that light is subtracted from a white piece of paper. This is achieved through the addition of more ink. The more ink that is added to paper, the more dark it gets. Key is added to achieve a true black colour. The CMYK colour space is mainly used for printing.

In CMYK, colors are applied to the paper one after the other in the proportion that will result in the required color. This means that in theory, about 4 billion colors can be created within CMYK. However with today’s technology, only a small portion of those can be displayed.

CMYK Color
The more color is used → the darker the final image will be. When Cyan, Magenta, and Yellow are all set to, the achieved color will be a very dark brown. This is why the Key color is required to create a true black.
Source: iPrintdifferent

What is the difference between RGB and CMYK?

Well, the main thing to remember is that RGB is used for electronic displays (cameras and monitors) and CMYK is used for printing.

Many customers create or edit their designs (intended for print) on design applications which use the RGB colour mode. This is because they are mainly used for design and image editing that usually end up on a computer screen. Hence, CMYK isn’t used (at least not as default).

The problem here is that when an RGB design is printed using a CMYK printing process, the colours appear differently (if not properly converted). This means that although a design might look absolutely perfect when the person views it on their desktop, there will often be colour discrepancies between the on-screen version and the printed version.

PDF RGB CMYK converting
Notice that between the 2 images, the blue and green translates differently on each image, this is due to the colour mode.
Source: PressPDF

Therefore, when you are designing or editing for print, you will be using the colours of RGB. To avoid unpleasant surprises, any files with RGB colors need to be converted to CMYK colors prior to photo printing.

Setting the right color space for photo printing

In some cases, you don’t need to convert from RGB to CMYK for the printing process, it all depends on the complexity of your design and the colours you’re using. But how exactly do you do this?

For Photoshop

To preview your file in CMYK without changing its color mode definitely, go to the Top Menu > View > Proof Colors. This will show you what the design is likely to look like when it’s been converted to CMYK.

Converting your file to CMYK in Photoshop

If you notice colour differences, you can use a Selective Colour adjustment to colour correct!

Selective Color - Possibly The Best Tool For Photographers | Fstoppers
Selective Color can be found in your Adjustment panels within Photoshop

This allows you to add blue hues to your shadows, gold/yellow tones to your highlights, and everything in between to help make your photo look great. 


Once you are satisfied with your final image, transform your file into CMYK colour mode go to Top Menu > Image > Mode > CMYK Color

Converting your file to CMYK in Photoshop

For Illustrator

Adobe Illustrator defaults to the CMYK colour mode but in case if it isn’t, you should follow the tutorial below:

Go to Top Menu> File > Document Color Mode > CMYK Color

Converting your file to CMYK in Illustrator

Note: If you are importing images to add to existing artwork or designs, these images will likely be in RGB format. You will need to convert these images to CMYK before saving.

Despite your best efforts to convert your files to CMYK, do note that there are a lot of variables other than colour space that can affect the print quality: calibration, paper type (weight, brightness, sheen/finish) and ink quality & levels.

We hope that this blog helps you understand the difference between RGB or CMYK and how to set your photos, images or files to CMYK mode if necessary. This is important in ensuring that what you see on the screen will remain true-to-life when printed!

When sending these photos to us here at Print For Fun for photo printing, be it in RGB or CMYK, you can be sure that your artwork or images can be printed in the highest quality possible!

For more information on getting your photos ready for printing, get in touch with our Print for Fun team at this email: [email protected]. If you wish for us to help you with editing, do drop us a mail too!

Hit us up on our Facebook or Instagram if you have any photo printing related questions you need answered.

Till next time, cheers!