SAMS Teach Yourself Adobe® Photoshop® CS2 in 24 Hours [Electronic resources] نسخه متنی

Finding Your Way Around

When you first open Photoshop, you'll see its toolbox on the left side of the screen, the Tool Options bar just under the menu headings at the top of the screen, several sets of floating palettes on the right, and a Welcome Screen in the middle with links to some introductory Help topics. (You'll also see your desktop, or whatever else is open at the time, if you use a Mac.) You won't see a work area because Photoshop, unlike many other programs, doesn't automatically open a new document for you. This actually makes sense because most of your work in Photoshop will be done on pictures that you have brought in from some other source. Maybe you'll be using digital images from your digital camera or scanner. Possibly you'll work on files you've downloaded from the Internet or on photos from a CD-ROM. In Hour 2, "Opening and Saving," you will learn all about opening these pictures. Right now, let's create a blank image document so that you can try some of Photoshop's tools.

Starting a New Image

FileNew is the first item on the first Photoshop menu. When you choose it, you open theNew dialog box, shown in Figure 1.1. You can enter a title for your new file at the top of the dialog box, such as New Image, or leave it untitled for now. The following sections provide a brief overview to get you started setting up a new file.

Image Size

The simple way to choose an image size is to use the Preset pop-up menu. It lists common American and European paper sizes, monitor sizes, and DVD screen sizes. Photoshop CS2 also includes a wide selection of TV and video formats, including PAL and HDTV screen sizes. Of course, you can also specify the size of your imagewidth and heightin pixels, inches, centimeters, points, picas, or columns across. These units are available in pop-up menus that you can access by clicking the small arrow next to the unit of measurement. See Figure 1.2.

For now, choose Default Photoshop Size. This gives you a 7x5 inch work area, a convenient size for most projects.

It's Magic! If you have an image copied on the Clipboard, when you create a new document, the dialog box will automatically show the size of the copied image.

Resolution

Resolution refers to the number of dots-of-ink-per-inch (if you're printing) or pixels-per-inch (if you're looking at the computer screen). It's important because the resolution of the image determines the quality. Higher resolution gives you a better quality image but uses more memory. Most images that you see in print have a resolution of 150 ppi to 300 dpi (dots per inch).Hour 5, "Color Modes and Color Models.")

Set the Background Contents to White. This gives you a white "canvas" to paint on.

Plan Ahead… If you intend to publish your images on the Web, ignore resolution completely. Rather than thinking of an image as "so-many-inches by so-many-inches at 72 ppi," think of the image as being "this-many-pixels by this-many-pixels." Consider how much of the Web page the image will cover. If, on the other hand, you are printing to a high-quality color inkjet or laser printer, set the resolution to 200 ppi. You should use 300 ppi only if you need to create professional color prints.

After you click OK in the New dialog box, you will see a new window. This is the

active window , and the

canvas is the large white square within it. You can have more than one window open within Photoshop at the same time, but only one can be the active window. The active window is always in the foreground. This is where you create and edit images.

Set your mouse pointer at the lower-right corner of the window, and then click and drag. The window expands, but notice that the canvas size stays the same. After you have created a new file, you can change the size of the canvas only by choosing ImageCanvas Size. This command enables you to specify a new height and width for the canvas, as shown in Figure 1.3. The Anchor section enables you to specify the base area from which the canvas expands or shrinks, by clicking any of the nine squares. (Changing the image size, obviously, changes the size of the canvas, too. The difference is that changing the canvas size gives you more room around your existing image.)

The Relative check box is a very useful tool. Checking the Relative box enlarges the canvas to create a border effect around the contents. It's useful if you have several differently sized photos and want to place them all in identical frames for a web page or printed document. Choose an appropriate size, such as 2% for a narrow frame, and enlarge all your pictures by the same percentage.