Creating and Managing Images with Photoshop Elements
One of the first things you'll be doing in Photoshop Elements is setting up your image. This involves creating a new file (or importing a photo or image from a digital camera, camcorder, or scanner), setting its dimensions and size, and arranging it on your desktop in a way that works best for you. Photoshop Elements can seem a little overwhelming at first, presenting you with almost too many settings choices when you first start working on an image. While you're welcome to adjust your image's resolution and print size to your heart's desire, you can also choose to skip this information for now if you just want to start correcting or retouching your photos. That's the beauty of Photoshop Elements. It offers an enormous amount of control and precision over your images, no matter how large or small the task.
Understanding Resolution and Image Size
Resolution and image size are frequently used and often misunderstood terms.
Resolution simply refers to the number of physical pixels, or picture elementstiny, square, building blocksthat are packed into a digital image.
Image size refers to both the print size and resolution of an image. Depending on whether you want to print a photograph, post it on a Web page, or e-mail it to a friend, you'll need to adjust its image size and resolution accordingly. This section explains the important relationship between image resolution and image size, and how to control these options to get the results you want.
Pixel basics
Everything you do in Photoshop Elements involves controlling and changing pixels. Pixelsindividual, tiny squares, or picture elementsmake up your entire image and are typically not visible as individual elements until you zoom in on your picture (Figure 2.1). In fact, Photoshop Elements may even have derived its name at least in part from these small but powerful image structures.
Figure 2.1 Pixels become visible as you increase the magnification of your image.
As you work in Photoshop Elements, you'll find that you need to adjust the size of your images for different projects. If you want to send a photo to a friend via e-mail, you'll want the file size to be as small as possible for easy deliveryso you'll want to create a low-resolution image, which means it contains a smaller number of pixels. If you're planning to print high-quality images on your ink-jet printer, then you'll want to maintain as high a resolution as your printer can handle (meaning a greater density of pixels), to ensure a crisp, clear print.
Images are often described using pixels as the unit of measure. For example, a common setting for many digital cameras is 1600 x 1200 pixels (the x is pronounced "by," just as in "3 x 5 photo"). Multiplying 1600 times 1200 gives us the total number of pixels in the image, which in this case is 1.92 million pixels.
Digital cameras often include preset resolution modes. These settings determine both the physical dimensions and file size of the image (Figure 2.2).
Figure 2.2 Examples of common digital camera resolutions and associated file sizes, all viewed at 100% (also referred to as actual pixels). Higher-resolution images, like the photo on top, provide a sharper, clear picture that's excellent for printing. Lower-resolution images, like the middle and bottom photos, lack sufficient pixel information for printing purposes, but work fine for posting on the Web or e-mailing to friends.
Displaying and printing images
Any discussion of resolution and output can be confusing, but you need to keep just a few basic details in mind. Image resolution is described in pixels per inch, or ppi. When you print your file, the printer resolution setting (or multiple settings) is usually described in dots per inch, or dpi.
The ideal amount of detail and level of resolution depend on how you intend to use an image. If you're going to be displaying your photos on the Web, keep in mind that large files take forever to download and view, so you'll want to stick with a lower resolution of 72 ppi (72 ppi is the most common image resolution for monitor displays).
Three factors affect the way that an image is displayed on a computer monitor: the number of pixels in the image, the screen resolution, and the screen size (Figure 2.3). The size of each pixel is determined by the resolution and size of the monitor. For example a 17-inch monitor set to a resolution of 1024 x 768 pixels would have 82 pixels per inch (Figure 2.4). The same monitor set to a resolution of 640 x 480 would have fewer pixels per inch, so each pixel takes up more screen space (Figure 2.5). If you change your monitor resolution to a lower resolution setting, the images and icons become bigger on your screen. This is because fewer pixels occupy the same space, and so the size of each pixel becomes bigger.
Figure 2.3 The display of an on-screen image is based on the resolution of the image, the size of the monitor, and the monitor resolution.
Figure 2.4 A monitor set to 1024 x 768 is a much more common setting, and allows program menus to be seen more easily.
Figure 2.5 The same monitor set to 640 x 480 displays fewer pixels per inch, so less of the image appears on your screen.
Printer resolution is usually described by the number of dots per inch that the printer is capable of printing. If you want to print a high-quality flyer or photo, you may need a resolution as high as 300 ppi. Fortunately, a wide range of resolutions are available that work well for different types of situations, and Photoshop Elements includes some automatic functions (such as the Save for Web command) that take the guesswork out of the process.