These days, everything is done over the computer – bill pay, socialization, even ordering take out. In most cases it’s cheaper, more efficient and more environmentally friendly. So it’s to no surprise that it’s now standard practice for graphic designers and print shops to provide digital proofs instead of an actual printed hard-copy proof. This is exceedingly more cost effective and the turnaround time is just about as fast as the designer can make the change and hit save. The only drawback of this process is that the client needs to be aware that the colors that they are seeing on the screen will slightly vary from the colors that they will see on the actual printed piece. This is due to the fact that the colors on your computer monitor are created using additive light (using the colors red, green, and blue (RGB))and output devices use subtractive light (using cyan, magenta, yellow, and black (CMYK)). Let’s explore the differences.
The additive color spectrum is produced by light directly emitted from a source, such as the small light beams within your computer screen. Because colors are coming directly from the light source, they tend to be more vibrant. It’s called additive because when you add red, green, and blue together in equal amounts, they create white. When you add any two of these primary colors, you get the secondary colors of the additive system which are cyan, magenta, and yellow.
On the other hand, output devices, such as printers, use the subtractive color system. These colors are created from light reflecting off of a surface (such as white paper). This is called subtractive because the surface subtracts the light waves that are not being reflected. In printing, the primary colors are cyan, magenta, and yellow. Black is then added to increase contrast. When mixed in equal parts, cyan, magenta and yellow will produce black. Because these colors are reflections from the light source, they tend to be less vibrant.
It’s a bit tricky to wrap your head around, but in short:
RGB
- Additive Color System: Starts with black, ends with white
- Produced directly from a light source
- More vibrant
CMYK
- Subtractive Color System: Starts with white, ends with black
- Produced by light reflecting off of a surface
- Less vibrant
Technology is improving and monitors can now be calibrated to better simulate the output of CMYK, but every monitor is different and will never be able to generate the exact same result. So, next time you’re reviewing an on-screen version of a print project, be aware that the colors you see on the screen do not mirror the exact outcome of the final printed piece.