Thursday, February 21, 2008


Hate to say I told you so, but..., oh wait I don't hate to say that, I love it. We had a discussion about why CMYK was used in the printing business instead of RGB. I said it was because CMYK was a deductive process whereas RGB is additive. Annom disagreed... Too bad dekus wasn't there because I think he would have settled it.
CMYK (short for cyan, magenta, yellow, and key (black), and often referred to as process color or four color) is a subtractive color model, used in color printing, also used to describe the printing process itself. Though it varies by print house, press operator, press manufacturer and press run, ink is typically applied in the order of the acronym.

The CMYK model works by partially or entirely masking certain colors on the typically white background (that is, absorbing particular wavelengths of light). Such a model is called subtractive because inks “subtract” brightness from white.

In additive color models such as RGB, white is the “additive” combination of all primary colored lights, while black is the absence of light. In the CMYK model, it is just the opposite: white is the natural color of the paper or other background, while black results from a full combination of colored inks. To save money on ink, and to produce deeper black tones, unsaturated and dark colors are produced by substituting black ink for the combination of cyan, magenta and yellow.


dekus said...

I was told that not only was it a " reverse" process (add ink to get white instead of getting black) but the RGB colors in ink was also physically hard to make and hard to work with.

Why I have no idea, but printing in CMYK was easier and cheaper although with RGB the color spectrum almost doubles.

annom said...

Interesting cybrbeast. My source actually was dekus.

Colours, and how they are created in our brain, are very interesting.

I think the answer to "why we use CMYK in printing", is that it is cheaper because subtractive methods are cheaper.
C M and Y result from the absorption of only one wavelength/colour, it probably is easier to find/make ink that absorbs only one colour instead of all wavelenghts except one wavelength/colour.

When you would print with RGB (+black), you have to print small non overlapping pixels. Like on a monitor, but than with a higher resolution -> smaller pixels. This is more expensive.

dekus said...

"My source actually was dekus."

Have I been lying again? ^.^