A life without colors ? Impossible for me.
Doing my job without colors? Also impossible for me.
Yes, colors represent a certain frequency of reflecting light.
Colors represent a certain temperature … like cold colors or warm colors, but hey they are so much more, never forget the psychological aspect of colors.
We will get back to that in another blog post.
What I have learned so far is, that we will never be able to display all colors nature shows us with our computers.
So we need color models.
Each model has its own purpose, meets different needs.
Don’t get confused, usually your image-processing program will help you with the color model. They even offer you different models at the same time.
So enjoy the rough overview on the 5 most popular models.
Just keep in mind, we are talking models, they are only used to display reality.
HSL and HSV
HSV stands for H = Hue, S = Saturation and V for Value.
HSL stands for H = Hue, S = Saturation and L for Lightness.
There are 2 other models called: HSB and HSI.
B means Brightness and I means Intensity.
HSV/HSL is a 3 dimensional model.
One axis is the color, which represents the frequency of the color and is measured in ° (e.g. blue 240°), another axis is saturation in adding more or less white light to the color and the 3rd axis is a certain light or dark value.
HSL is very close to the way humans realize colors in their daily life.
Lab color space
Another model trying to display the way humans see and realize colors.
Using this model colors are defined in a standard way, no matter what device is used for creating the color.
L means lightness, a is an axis that represents colors in the spectrum of green ↔ red and b is an axis with blue ↔ yellow.
The higher the L-value is the darker the color will appear.
A very important color model is:
RGB color model
Your TV and your monitor of your computer works with this model.
We call it additive color model.
It works with light.
We have 3 basic colors: Red, Green, Blue.
If you take 3 lamps with these colors and allow the light to meet in the middle you will get White.
We use to talk about 24 bit color depths, which means that the color is divided into 3 channel (RGB) of 8 bits and graduations from 0 to 255.
All channels 0 = black, all channels 255 = white.
Red = 255 R, 0G, 0B …
For printing we use the
CMYK color model
Contrary to RGB the CMYK model is a subtractive color model.
Mixing all colors together we will get black.
C = Cyan
M = Magenta
Y = Yellow
K = Key which stands for Black
You can get a full color range just with CMY, but to get a specific depth to the pictures.
The black printing plate is the key plate, all color plates are adjusted to the K-plate.
When printing you will need a plate for each color, but printing all colors together will create the picture.
Each country has its own standards for CMYK-Printing.
Europe uses Euroscale and the USA uses SWOP.
The density of each color is defined in %. The more you take of the color the deeper the print will be.
If you want to print a very light pink, you might just use 10% or 20% of magenta.
Final color model:
Hexadecimal color codes or Webcolors
A model based on RGB but using a 6-digit code to describe the color beginning each code with a hash #.
The code represents: #RRGGBB
The code is written with numbers and letters from 00 to FF.
#000000 = black
as no red, no green, no blue light means complete darkness = black.
#ffffff mixes all colors = R255, G255, B255 = maximum light = white.
#ff0000 = R255G0B0 = red.
The color code is used in programming websites via html.
The way we see colors is subjective.
Everybody has her own point of view.
But the models help us to describe the colors, and help to get standard results.
What is your favorite color?
Can you find the hexa-code or the CMYK value?
- Adolie Twins: Using CMYK and RGB (klacenklaiart.wordpress.com)
- A Simple Way to Understand Hue, Saturation and Luminosity (labnol.org)