Absolute Beginner's Guide to Digital Photography

As a reminder, the best Undo of all is to save a copy

of any image before you work on it. This is especially

important when working with compressed images

such as JPEG files. The first time you open a JPEG

file, for example, you should save it with a new

name as a TIFF or PSD file to save the original and

prevent further compression of the image.

Introduction to Selection Tools

The following examples use the full version of

Photoshop to prepare a digital file that is large

enough (in resolution and pixel size) to print on an

8''×10'' sheet of photo paper. The examples were

edited with Photoshop on a Windows computer; the

use of Photoshop on an Apple Macintosh computer

is very similar. These tools are similar in Photoshop

Elements on either platform. Follow these steps to

change the image size:

1. Open Photoshop or Elements. Open an existing image file by choosing File,
   Open. This exercise uses an image pulled from NASA’s Planetary
   Photojournal Web site (see Figure 10.3) at
   http://photojournal.jpl.nasa.gov/index.html.

136 ABSOLUTE BEGINNER’S GUIDE TODIGITAL PHOTOGRAPHY

Every image you open

in Photoshop should be

saved with a new name to pre-

serve the original. Form a habit of

saving images with a new name

immediately after opening. You

will thank yourself later when

your machine crashes, the power

goes out, or your image file

becomes corrupted.

FIGURE 10.3

A test image

downloaded

from NASA’s

Planetary

Photojournal.