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Chapter 1 ✦ Introducing Photoshop CS2
As luck would have it, Photoshop bridges the gap between conventional painting
and drawing programs quite nicely by providing many of the best features of both.
In addition to its wealth of image-editing and organic-painting capabilities, Photoshop
permits you to add vector-based text and shapes to your photographic images.
These features may not altogether take the place of a drawing program, but they help
to make Photoshop an increasingly flexible and dynamic image-creation environment.
The ups and downs of painting
As you might expect, painting programs and drawing programs have their own
strengths and weaknesses. The strength of a painting program is that it offers a
straightforward approach to creating images. For example, although many of
Photoshop’s features are complex — some of them extremely so — its core painting
tools are as easy to use and familiar as a pencil. You alternately draw and erase until
you reach a desired effect, just as you’ve been doing since childhood.
In addition to being simple to use, each of Photoshop’s core painting tools is fully
customizable. It’s as if you have access to an infinite variety of crayons, colored
pencils, pastels, airbrushes, watercolors, and so on, all of which are erasable. The
simplicity and customization potential make these tools fun to use, and you’ll find
yourself creating artwork that you would never have had the time or patience to
attempt manually.
Because painting programs rely on pixels, they are ideally suited to electronic
photography. Whether captured with a scanner or digital camera, an electronic
photograph is composed of thousands or even tens of millions of colored pixels.
A drawing program such as Illustrator may let you import such a photograph and
apply very simple edits, but Photoshop gives you complete control over every pixel,
entire collections of pixels, or independent elements of pixels. As witnessed by a
quick examination of the pictures in this book, a photograph can become anything.
The downside of paintings and electronic photos is that they are ultimately finite
in scale. Because a bitmap contains a fixed number of pixels, the resolution of an
image — the number of pixels in an inch, a centimeter, or some other defined space —
changes with respect to the size at which the image is printed. Print the image small,
and the pixels become tiny, which increases the resolution of the image. Like the
millions of cells in your body, tiny pixels become too small to see and thus blend
together to form a cohesive whole, as in the first image in Figure 1-1. Print the image
large and the pixels grow, which decreases the resolution. Large pixels are like cells
viewed through a microscope; once you can distinguish them independently, the
image falls apart, as in the second example in the figure. The results are jagged edges
and blocky transitions. The only way to remedy this problem is to increase the num-
ber of pixels in the image, which increases the size of the file.
Bear in mind that this is a very basic explanation of how images work. For a more
complete description that includes techniques for maximizing image resolution
and quality, check out Chapter 3.
Cross-
Reference
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