Digital Prints

2
Understanding
Digital Printing
At its core, digital printing is simple. A binary data stream drives a print engine to render
a digital image on an output device. End of story? Not quite. Like any production process,
digital printing requires the right tools and the right information to make the right choices.
Let’s begin at the beginning.
A Digital Primer
Photographers and artists are all, basically, image makers, so let’s start by looking inside a
digital image.
Anatomy of a Digital Image
First things first. Ninety-five percent of all the images that photographers and artists end
up printing digitally are binary images, also called raster images, also called pixel-based
images, also called bitmaps. Confused yet? The term bitmap itself sends some people running
for shelter. One reason is because Adobe Photoshop, considered the top imageediting
software program, has a mode option called “bitmap” that converts an image into
the crudest (1-bit per pixel) form. That’s unfortunate because there’s a lot more to bitmaps
than that. In fact, bitmaps are the key to the Chamber of Secrets of digital printing.
To put it simply, a bitmapped image is a collection of pixels (picture elements) arranged
on a rectangular grid (it’s a map of a bunch of bits); see Figure 2.1. Each pixel can be
described or “quantized” in terms of its color and its intensity or value. The more pixels
there are and/or the more the depth of information per pixel, the more binary digits (the
little ones and zeros that the computer understands) there are, and the more detailed the
image (see “Pixels and Bit Depth” for more about this).