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115 Chapter 3 ✦ Image Fundamentals Figure 3-21: After adding text-based notes or audio comments to an image, save the file in the PDF format so that others can access the annotations when viewing the image in Adobe Acrobat. When you save your image, be sure to save in the Photoshop native format or PDF and select the Annotations check box in the Save dialog box. Otherwise, you lose all your notes. For information on how to delete individual notes in an open image and how to customize and import notes, skip to the section “Managing annotations.” Voicing your opinions If you like to speak your mind rather than put your thoughts in writing, check out the audio annotation tool. This tool works like the notes tool except that it inserts an audio recording of your voice rather than a text message into the file. Of course, you need a microphone, speakers, and a sound card installed in your computer to use this feature. Also, Photoshop retains audio annotations only when you save the image file using the Photoshop native format or PDF, as with text notes. Be aware, too, that audio files increase file size significantly. The audio annotation tool shares quarters with the notes tool in the toolbox. Press N to toggle between the two tools (or Shift+N, depending on the preference you established in the General panel of the Preferences dialog box). Click in your image at the spot where you want the icon representing your message to appear. 6 Photoshop 6 Note icon Open note 116 Part I ✦ Welcome to Photoshop 6 When the Audio Annotation dialog box appears, click Start to begin your recording and then talk into the microphone. Click Stop when you’ve said all you have to say. Photoshop represents your audio message with a little speaker icon in the image window. Double-click the icon to play the message. Managing annotations If you’re a solo artist and the only approval of your work you need is your own, you may not have much reason to use the notes or audio annotation tools. Then again, you may be an easily distracted sort and find annotations a terrific way to remind yourself exactly what you’re trying to accomplish in an image. And who’s to say that your friends won’t love being able to hear an audio clip of your dog Binky yapping at the vacuum cleaner when they view his picture in Acrobat? Whether you’re using annotations for fun or profit, use the following strategies to manage audio and text annotations: ✦ Use the Font and Size controls on the Options bar to change the font and type size in an open note. ✦ Click the Color icon to change the color of the icon and title bar for any new note you create. This option comes in handy if several people will be review- ing the image and putting in their two cents’ worth. You can assign a different color to each author. To change the color of an existing note, open the note and click the Color icon. This time, you affect only the open note — other notes by the same author don’t change. ✦ You can move and copy annotations between image windows. Just click the icon and use the Cut, Copy, and Paste commands as you do to move and copy any selection. ✦ If an icon blocks your view of the image, you can drag it out of the way. However, when you open the note, its window appears in the icon’s original location. Drag the size box in the lower-right corner of an open note to shrink the window if necessary. ✦ Choose View➪ Show➪ Notes to toggle the display of annotation icons on and off. Alternatively, choose View ➪ Hide All and View ➪ Show All to hide and display icons and other interface elements such as selection marquees, guides, and so on. ✦ To delete a single annotation, click its icon and press Delete. Or right-click the icon and choose Delete Note. If you want to delete all annotations, choose Delete All Notes or click the Clear All button on the Options bar. If you send out several copies of the same image for approval, you don’t have to open each copy individually to read the annotations. Instead, open just one copy and then import the annotations from the other files. Choose File ➪ Import ➪ Annotations, select the files containing the annotations, and click Open. Photoshop gathers up all the annotations and dumps them into your open image. Tip 6 Photoshop 6 117 Chapter 3 ✦ Image Fundamentals Remember to save your image in the PDF or Photoshop 6 file format to retain annotations in a file. And if you’re sending an annotated file to other people for viewing, tell them that they need to use Adobe Acrobat 4.0 or higher to access the annotations. Resampling and Cropping After you bring up an image —whether you created it from scratch or opened an existing image stored in one of the five billion formats discussed in the preceding pages —its size and resolution are established. Neither size nor resolution is set in stone, however. Photoshop provides two methods for changing the number of pixels in an image: resampling and cropping. Resizing versus resampling Typically, when folks talk about resizing an image, they mean enlarging or reducing it without changing the number of pixels in the image, as demonstrated back in Figure 3-1. By contrast, resampling an image means scaling it so the image contains a larger or smaller number of pixels. With resizing, an inverse relationship exists between size and resolution—size increases when resolution decreases, and vice versa. But resampling affects either size or resolution independently. Figure 3-22 shows an image resized and resampled to 50 percent of its original dimensions. The resampled and original images have identical resolutions, but the resized image has twice the resolution of its companions. Resizing an image To resize an image, use one of the techniques discussed in the “Changing the print- ing resolution” section near the beginning of this chapter. To recap briefly, the best method is to choose Image ➪ Image Size, turn off the Resample Image check box, and enter a value into the Resolution option box. See Figure 3-2 to refresh your memory. Resampling an image You also use Image➪ Image Size to resample an image. The difference is that you leave the Resample Image check box turned on, as shown in Figure 3-23. As its name implies, the Resample Image check box is the key to resampling. When Resample Image is selected, the Resolution value is independent of both sets of Width and Height values. (The only difference between the two sets of options is that the top options work in pixels and the bottom options work in relative units of measure such as percent and inches.) You can increase the number of pixels in an image by increasing any of the five values in the dialog box; you can decrease the number of pixels by decreasing any value. Photoshop stretches or shrinks the image according to the new size specifications. Caution 118 Part I ✦ Welcome to Photoshop 6 Figure 3-22: An image (top) resized (bottom left) and resampled (bottom right) down to 50 percent. The resized image sports a higher resolution; the resampled one contains fewer pixels. At all times, you can see the new number of pixels Photoshop will assign to the image, as well as the increased or decreased file size. In Figure 3-23, for example, I’ve changed the first Width value to 56 percent. The Pixel Dimensions value at the top of the dialog box reflects my change by reading 5.12M (was 16.3M), which shows that the file size has decreased. To calculate the pixels in the resampled image, Photoshop must use its powers of interpolation, as explained in the “General preferences” section of Chapter 2. The interpolation setting defaults to the one chosen in the Preferences dialog box. But you can also change the setting right inside the Image Size dialog box. Simply select the desired method from the Resample Image pop-up menu. Bicubic results in the smoothest effects. Bilinear is faster. And Nearest Neighbor turns off interpolation so Photoshop merely throws away the pixels it doesn’t need or duplicates pixels to resample up. Original Resized Resampled 119 Chapter 3 ✦ Image Fundamentals Figure 3-23: With the Resample Image check box turned on, you can modify the number of pixels in your image. Here are a few more random items you should know about resampling with the Image Size dialog box: ✦ This may sound odd, but you generally want to avoid adding pixels. When you resample up, you’re asking Photoshop to make up details from thin air, and the program isn’t that smart. Simply put, an enlarged image almost never looks better than the original; it merely takes up more disk space and prints slower. ✦ Resampling down, on the other hand, is a useful technique. It enables you to smooth away photo grain, halftone patterns, and other scanning artifacts. One of the most tried-and-true rules is to scan at the maximum resolution permitted by your scanner and then resample the scan down to, say, 72 or 46 percent (with the interpolation set to Bicubic, naturally). By selecting a round value other than 50 percent, you force Photoshop to jumble the pixels into a regular, homogenous soup. You’re left with fewer pixels, but these remaining pixels are better. And you have the added benefit that the image takes up less space on disk. ✦ To make an image tall and thin or short and fat, you must first turn off the Constrain Proportions check box. This enables you to edit the two Width values entirely independently of the two Height values. Tip 120 Part I ✦ Welcome to Photoshop 6 ✦ You can resample an image to match precisely the size and resolution of any other open image. While the Image Size dialog box is open, choose the name of the image you want to match from the Window menu. ✦ If you need help resampling an image to the proper size for a print job, choose Help ➪ Resize Image to bring up the Resize Image Wizard. The dialog box walks you through the process of resampling step by step. It’s really for rank beginners, but you might find it helpful when you want to turn the old brain off and set Photoshop to autopilot. (Note that Adobe uses the word “resize” simply because it’s friendlier than “resample.” Whatever it’s called, this command does indeed resample.) If you ever get confused inside the Image Size dialog box and you want to return to the original size and resolution settings, press the Alt key to change the Cancel button to Reset. Then click the Reset button to start from the beginning. Photoshop remembers the setting of the Resample Image check box and uses this same setting the next time you open the Image Size dialog box. This can trip you up if you record an action for the Actions palette, as discussed in Chapter B on this book’s CD-ROM. Suppose that you create an action to resize images, turning Resample Image off. If you later resample an image —turning on Resample Image— the check box stays selected when you close the dialog box. The next time you run the action, you end up resampling instead of resizing. Always check the status of the check box before you apply the Image Size command or run any actions containing the command. Cropping Another way to change the number of pixels in an image is to crop it, which means to clip away pixels around the edges of an image without harming the remaining pixels. (The one exception occurs when you rotate a cropped image or use the new perspective crop feature, in which case Photoshop has to interpolate pixels to account for the rotation.) Cropping enables you to focus on an element in your image. For example, Figure 3-24 shows a bit of urban graffiti from a Digital Stock CD. I like this fellow’s face —good chiaroscuro —but I can’t quite figure out what’s going on with this guy. I mean, what’s with the screw? And is that a clown hat or what? That’s the problem with graffiti— no art direction. Luckily, I can crop around the guy’s head to delete the extraneous image elements and hone in on his sleepy features, as shown in Figure 3-25. Version 6 offers several new, cutting-edge cropping options —har har—including the capability to crop nonrectangular selections, automatically trim away transparent areas from the borders of an image, and correct perspective effects while cropping. You can read about all these features in the upcoming sections. 6 Photoshop 6 Caution Tip 121 Chapter 3 ✦ Image Fundamentals Figure 3-24: This image contains too much extraneous information. Where should my eye go? I’m so confused. Figure 3-25: Cropping enables you to clean up the background junk and focus on the essential foreground image. Changing the canvas size One way to crop an image is to choose Image➪ Canvas Size, which displays the Canvas Size dialog box shown in Figure 3-26. The options in this dialog box enable you to scale the imaginary canvas on which the image rests separately from the image itself. 122 Part I ✦ Welcome to Photoshop 6 Figure 3-26: Choose Image ➪ Canvas Size to crop an image or to add empty space around the perimeter of an image. If you enlarge the canvas, Photoshop surrounds the image with a white background (assuming the background color is white). If you reduce the canvas, you crop the image. Click inside the Anchor grid to specify the placement of the image on the new canvas. For example, if you want to add space to the bottom of an image, enlarge the canvas size and then click inside the upper-middle square. If you want to crop away the upper-left corner of an image, create a smaller canvas size and then click the lower-right square. The Anchor grid offers little arrows to show how the canvas will shrink or grow. To shrink the canvas so that it exactly fits the image, don’t waste your time with the Canvas Size dialog box. Using a nifty new command, Image ➪ Trim, you can automatically clip away empty canvas areas on the outskirts of your image. When you choose the command, the dialog box shown in Figure 3-27 appears. To snip away empty canvas, select the Transparent Pixels radio button. Then specify which edges of the canvas you want to slice off by using the four Trim Away check boxes. Alternatively, you can tell Photoshop to trim the image based on the pixel color in the top-left corner of the image or the bottom-right corner — just click the appropriate Based On radio button. For example, if you have a blue stripe running down the left edge of your image and you select the Top Left Pixel Color radio button, Photoshop clips away the stripe. No trimming occurs unless the entire edge of the image is bounded by the selected color. When you want to enlarge the canvas but aren’t concerned with making it a specific size, try this time-saving trick: Drag with the crop tool to create a crop marquee and then enlarge the crop marquee beyond the boundaries of the image (see the next section if you need help). When you press Enter to apply the crop, the canvas grows to match the size of the crop marquee. Tip 6 Photoshop 6 123 Chapter 3 ✦ Image Fundamentals Figure 3-27: To quickly snip away transparent areas from the edges of an image, use the new Image ➪ Trim command. Using the crop tool Generally speaking, the Canvas Size command is most useful for enlarging the canvas or shaving a few pixels off the edge of an image. If you want to crop away a large portion of an image, using the crop tool is a better choice. Press C or click the crop icon in the toolbox to activate the tool. The crop tool regains its own slot in the toolbox in Version 6, which means that you no longer have to slog through the marquee flyout menu to select the tool. And that’s just the beginning of the changes to the crop tool. You still drag with the tool to create a rectangular marquee that surrounds the portion of the image you want to retain. But you can control what happens during and after you crop in two important ways: ✦ To help you distinguish the borders of the crop marquee, Photoshop displays a colored, translucent overlay on the area outside the crop box—similar to the way it indicates masked versus unmasked areas when you work in the quick mask mode. Hate the overlay? Deselect the Shield Cropped Area check box on the Options bar. You also can click the neighboring color box to change the overlay and set the overlay opacity through the Opacity pop-up menu. Note that these controls don’t appear on the Options bar until after you create your initial crop marquee. ✦ You now have the option of permanently discarding the pixels you crop or simply hiding them from view. Before you drag with the crop tool, click the Delete or Hide radio button on the Options bar to signify your preference. If you choose Hide, you can bring the hidden regions back into view by enlarging the canvas or by using the new Image ➪ Reveal All command. As you drag, you can press the spacebar to move the crop boundary temporarily on the fly. To stop moving the boundary and return to resizing it, release the spacebar. Tip 6 Photoshop 6 124 Part I ✦ Welcome to Photoshop 6 If you don’t get the crop marquee right the first time, you can move, scale, or rotate it at will. Here’s what you do: ✦ Drag inside the crop marquee to move it. ✦ Drag one of the square handles to resize the marquee. You can Shift-drag a handle to scale the marquee proportionally (the same percentage vertically and horizontally). ✦ Drag outside the crop marquee to rotate it, as explained in the next section. This may strike you as weird at first, but it works wonderfully. ✦ Drag the origin point (labeled in Figure 3-28) to change the center of a rotation. Figure 3-28: Align the crop marquee with an obvious axis in your image to determine the proper angle of rotation. ✦ Select the Perspective check box on the Options bar, and you can drag corner handles to distort the image. What’s the point? Well, the primary reason to use this option is to correct convergence problems that often occur when you take pictures using a wide-angle lens. Vertical structures along the edges of the image tend to lean one way or another due to the design of the lens. 6 Photoshop 6 Origin point Crop marquee Handles Rotate cursor [...]... substandard detail) — to see how each channel might look on its own To browse the channels, press Ctrl+1 for red, Ctrl+2 for green, and Ctrl+3 for blue Or Ctrl+1 for cyan, Ctrl+2 for magenta, Ctrl+3 for yellow, and Ctrl+4 for black Or even Ctrl+1 for luminosity, Ctrl+2 for a, and Ctrl+3 for b Chapter 16 describes color channels in more detail Black and white (bitmap) Choose Image ➪ Mode ➪ Bitmap to convert... and Retouching Furthermore, you can save an RGB image in every file format supported by Photoshop except GIF and the two DCS formats As shown in Table 4-1, grayscale is the only other color mode compatible with a wider range of file formats Table 4-1 File-Format Support for Photoshop 6 Color Models Bitmap Duotone Indexed RGB Lab CMYK Photoshop Yes Yes Yes Yes Yes Yes Yes BMP Yes Yes No Yes Yes No No... the prefab gradients available through the gradient styles pop-up menu) 6 Photoshop fills any shapes you create with the new shape tool with the foreground color You can apply the foreground color to a standard selection by choosing Edit ➪ Fill or Edit ➪ Stroke or by pressing Alt+Backspace To change the foreground color, click the foreground color icon to display the Color Picker dialog box, select a... preceding paragraph 125 1 26 Part I ✦ Welcome to Photoshop 6 Cropping an image to match another There are two ways to crop an image so it matches the size and resolution of another image: ✦ Bring the image you want to crop forward and choose Image ➪ Canvas Size Then, while inside the Canvas Size dialog box, select the name of the image you want to match from the Window menu Photoshop Tip 6 This method doesn’t... canvas (If you save the image in a file format other than the native Photoshop format, however, hidden pixels are abandoned forever.) One advantage of the Crop command is that you needn’t switch back and forth between the marquee and crop tools One tool is all you need to select and crop (If you’re as lazy as I am, the mere act of selecting a tool can prove more effort than it’s worth.) And, as with the... and Retouching Specifying colors First off, Photoshop provides four color controls in the toolbox, as shown in Figure 4-1 These icons work as follows: Photoshop ✦ Foreground color: The foreground color icon indicates the color you apply when you use the type, paint bucket, line, pencil, airbrush, or paintbrush tool, or if you Alt-drag with the smudge tool The foreground color also begins any gradation... details by hand Photoshop applies your changes more slowly in the CMYK mode, but at least you’re only slowed down at the end of the job, not throughout the entire process Photoshop CrossReference Before converting an image to the CMYK color space, make certain Photoshop is aware of the monitor you’re using and the printer you intend to use These two items can have a pronounced effect on how Photoshop generates... displays 65 ,000 variations on the slider color; 2 56 times 65 ,000 is 16 million No matter which radio button you select, you have access to the same colors; only your means of accessing them changes ✦ Current color: The color currently selected from the color field appears in the top rectangle immediately to the right of the color slider Click the OK button or press Enter to make this the current foreground... Colors 360 ° Hue Brightness 100% 0% 0° 0% Saturation 100% 100% Saturation Brightness 100% 0% 0% 0° Hue 360 ° 100% 100% Saturation Brightness 0% 0% 0° Hue 360 ° Figure 4-3: The color field graphs colors against the two attributes not represented in the slider Here you can see how color is laid out when you select (top to bottom) the H (Hue), S (Saturation), and B (Brightness) radio buttons 135 1 36 Part... couldn’t afford this big, fat book if we’d printed it in full color So I recommend you experiment with the Color Picker inside your version of Photoshop or refer to Color Plate 4-1 to see how the dialog box looks when the H (Hue), S (Saturation), and B (Brightness) options are selected Note Slider and field always work together to represent the entire 16 million color range The slider displays 2 56 colors, . Photoshop gathers up all the annotations and dumps them into your open image. Tip 6 Photoshop 6 117 Chapter 3 ✦ Image Fundamentals Remember to save your image in the PDF or Photoshop 6 file format. where you want the icon representing your message to appear. 6 Photoshop 6 Note icon Open note 1 16 Part I ✦ Welcome to Photoshop 6 When the Audio Annotation dialog box appears, click Start to. get the placement and size exactly right — the only thing you can’t do is rotate. 6 Photoshop 6 Note 6 Photoshop 6 Tip 127 Chapter 3 ✦ Image Fundamentals Another advantage of the Crop command is