tailieunhanh - Understanding Adobe Photoshop CS4- P3

Understanding Adobe Photoshop CS4- P3: Learning Adobe Photoshop is essential to success in digital media industries. Photoshop is a gateway into several related technologies. From digital image acquisition and processing to typography and compositing, Photoshop is often your fi rst introduction. If you can master this program, you can go on to success with several other technologies. With this in mind, it is important to learn Photoshop with one eye on the present and the other on the future. | 48 Chapter 4 Sizing Digital Images 7. Click the Commit button or press Return Enter. The resulting image should appear as if the photo was squared and the camera was level. Rotate Canvas Command Sometimes your image will need to be rotated or flipped. Loading your image upside down on the scanner loading a slide backwards into a slide scanner or turning the camera on its side when taking a portrait often causes inverted or reverse images. You may also want to make a change to your image for compositional purposes. The Rotate Canvas command offers several choices. You can choose to rotate the image 180 half a rotation 90 clockwise or counterclockwise or an arbitrary amount the user types in a number of degrees . Additionally the entire canvas can be flipped creating a mirrored image . You can choose to flip the canvas horizontally or vertically 1. Open the image from the Chapter 4 folder. 2. Choose Image Rotate Canvas 90 CCW counterclockwise . The image is now properly oriented. Free Transform Command The Free Transform command is another useful way to rotate and size an image. It works best when you have an object located on its own layer or if you have an active selection. You ll explore selections and layers in much greater detail in future chapters. For now let s work with a simple layered image that has already been prepped. Resizing an Image 49 1. Open the file Ch04_Free_Transform_ . 2. This image has two layers a background which is a gradient and a vector shape layer. A vector layer is a special layer in Photoshop. It can be resized and transformed repeatedly with no degradation in quality. Vector layers use math to describe curves and can be freely manipulated. 3. If it s not visible call up the Layers panel by selecting Windows Layers. 4. Select the Vector Shape layer so it is active. 5. Choose Edit Free Transform or press Command Ctrl T. You can access several controls for the Free Transform command by right-clicking .