What is a Pixel?

Concept of  Pixel

See the youtube video on this topic:  Make Shop Pro - Exploring the Pixel

As it pertains to image editing and digital art, the pixel can be thought of as the atomic particle of an image.  All images (as displayed) are a rendering of a grid of pixels of varying hue and luminance.  The hue and luminance are its attributes, and the simplest analogy of this concept is to think of a pixel as a bucket of light.  And within that bucket are smaller buckets which only hold specific color conponents of the light.

Luminance Values

These buckets have limits.  The largest number of "light values" a bucket can hold is 255, with the least being zero.  In this way, 255 is the brightest a bucket can be and zero is the darkest, or pure black.

All colors that a pixel can assume are represented by varying degrees of 0-255 values for the different primary colors Red, Green and Blue (or RGB).  From a data point of view, a color is often denoted as a hexadecimal number (i.e. #12AF98).  The red, green, and blue values are associated with this number in the order of #RRGGBB.  So for example, some example colors values are shown below:

• Red:  #FF0000
• Green:  #00FF00
• Blue:  #0000FF
• White:  #FFFFFF
• Black:  #000000

Grayscale values are present whenever the value of each primary color is the same, so all of the following values are different levels of gray:

• #AFAFAF
• #202020
• #1B1B1B

Color Picker Tool

The color picker tool is a great tool for viewing the color of a pixel.  By hovering over any part of an image you can get an idea of what the RGB components are.  Note however that as you work with these RGB colors, that this is an additive color system.

Additive Color System

To explain an additive color system it is best to first explain it's opposite, the subtractive color system.  A substractive color system explains how colors blend similar to the way we understand paint colors mixing.  This system is based on what colors are absorbed vs what is reflected.  Some examples are below:

• Red + Green = Brown
• Red + Blue = Purple
• Yellow + Blue = Green
• Yellow + Red = Orange
• All colors combined = dingy brown

The additive color system is more similar to how colored lights combine to make color.  In this way color combining is a bit different.  Some examples are below:

• Red + Green = Yellow
• Red + Blue = Magenta
• Green + Blue = Cyan
• Red + (less) Green = Orange
• All colors combined = White

Conclusion

In conclusion, it's worth noting how these pixels behave.  That they have luminance value ranges from 0-255 and that the way colors combine are in an addivitve color system.  These elements are useful when navigating the many tools in PaintShop Pro where these concepts and values appear.

The hope is that familiarity will help you as a Digital Artist.