Adobe Photoshop CS5 One-on-One

The Vector-Based Duo

Generally speaking, Photoshop brokers in pixels, or raster
art. But the subjects of this lesson are something alto-
gether different. Photoshop treats both text and shapes as
vector-based objects (or just plain vectors), meaning that
they rely on mathematically defined outlines that can be
scaled or otherwise transformed without any degrada-
tion in quality.

For a demonstration of how vectors work in Photoshop,
consider the composition shown in Figure 11-2. The Q is
a text layer with a drop shadow. The black crown and the
orange fire are shapes. The background is a pixel-based
gradient. The artwork looks jagged because it contains
very few pixels. The image measures a scant 50 by 55
pixels (less than 2800 pixels in all) and is printed at just
15 pixels per inch!

Clearly, you’d never create such low-resolution artwork in
real life. I do it here to demonstrate a point: If this were
an entirely pixel-based image, we’d be stuck forever-
more with jagged, indistinct artwork. But because the
Q, crown, and fire are vectors, they are scalable. In other
words, unlike pixel art, vectors become smoother when
you make them bigger.

One way to scale the vectors is to print them to a PostScript-
compatible printer, which automatically scales the art-
work to the full resolution of the device. The result is a
breathtaking transformation. Believe it or not, the low-
resolution, jagged artwork from Figure 11-2 prints to a
PostScript output device as shown in Figure 11-3. All
pixel-based portions of the composition—namely, the
gradient and drop shadow—print just as they look on
screen. But Photoshop conveys the text and shapes as
true PostScript vectors; therefore, they render at the full
resolution of the printer.

Few people own PostScript printers; most of us are stuck
with standard raster printers. (Your everyday average
inkjet device prints just the pixels you see on screen, as

An incredibly low-res composition

(50 x 55 pixels), rendered at 15 ppi

The very same low-res file,

output from a PostScript printer

Figure 11-2.

Figure 11-3.

The Vector-Based Duo 375