Tài liệu Photoshop cs5 by Dayley part 55 pdf

Chapter 12: Adjustment Workflow 373 The bottom line here is that you can use the Auto adjustments for a quick fix that might actually work if you take the time to figure out which setting is best with each individual image. Does this sound like too much work for something that was supposed to be easy? I think so too. Stick to cus- tom adjustments; you’ll have less to remember, and your images will look better in the long run. Using the Adjustments Panel The Adjustments panel is your one-stop shop to quickly click an adjustment layer over your image. I’ve already introduced you to the icon in the Layers panel that allows you to add a fill or adjustment layer—the half-black, half-white circle. The Adjustment panel is accessed with the same icon, as shown in Figure 12.2. FIGURE 12.2 The Adjustments panel Adjustment name Adjustment icons Adjustment panel icon Return to controls for current adjustment layer New adjustments affect all layers or clip to layer below Expand adjustment panel 19_584743-ch12.indd 37319_584743-ch12.indd 373 5/3/10 10:33 AM5/3/10 10:33 AM Part IV: Enhancing, Correcting, and Retouching 374 Tip If you are correcting photos often, you probably spend lots of time with the Adjustment panel. Use the Photography workspace to quickly readjust your panels so that the Adjustment panel is in the main panel area above the Layers panel. If you are unsure how to do this, review workspace presets in Chapter 2. n Adjustment icons The upper portion of the Adjustment panel is dominated by the Adjustment icons. Although they are not labeled, you will soon get the hang of which is which. To get started, hover over and high- light each of them and watch the name appear in the Adjustment name area of the panel. These adjustments are found in the Adjustment panel: l Brightness/Contrast: This option gives you two basic sliders. The first adjusts the bright- ness of the image, unilaterally enhancing or reducing the brightness of the pixels. The sec- ond adjusts the contrast, changing the value of the midtones in the image by making the tones on the dark side 50 percent darker and the tones on the light side lighter. l Levels: You can adjust the levels of the brightness values in your file by adding a Levels layer to it. As you choose the Levels option, you see a histogram that represents the bright- ness values found in your file. By adjusting the sliders, you can increase (or decrease) the darkness of your darkest pixels or increase the brightness of your brightest pixels. You can do this in all the color channels together or in each one individually. l Curves: The curves option allows you to add up to 14 points along the tonal range from shad- ows to highlights. The dialog box also includes a preset menu to give you a jumping-off point. l Exposure: The Exposure option is meant to correct exposure problems in your image. Change the Exposure, Offset, and Gamma Correction to give your file highlights or dark tones similar to overexposing or underexposing a picture. l Vibrance: This option works selectively to saturate areas of your image that have less color while leaving already saturated areas alone. l Hue/Saturation: This option allows you to change the hue, saturation, or lightness of the different color channels contained in your file or all of them at once. You can use a drop- down list to choose a color range or use the eyedropper to customize the color you change. l Color Balance: The Color Balance panel gets right to the point. You can change the levels of the color channels in your file using the Highlights, Midtones, or Shadows. This is the easiest way to directly affect individual colors in your file. l Black & White: This option gives you the most power in creating a black and white image from a color photo. The Black & White adjustment includes options that let you set the levels of the colors in your image so that they are mapped to the grayscale values that you choose. l Photo Filter: Using a Photo Filter on your image mimics using the same filter on your camera. You can use one of 20 preset filters or change the color of the filter using the Select Filter Color dialog box. l Channel Mixer: The Channel Mixer lets you adjust the color levels in each channel sepa- rately. A drop-down menu gives you several preset options. 19_584743-ch12.indd 37419_584743-ch12.indd 374 5/3/10 10:33 AM5/3/10 10:33 AM Chapter 12: Adjustment Workflow 375 l Invert: The Invert option changes all the colors in your file to their exact opposite, creat- ing a negative image. The Invert adjustment doesn’t have any panel controls; it simply changes every color to 255 minus its original value. l Posterize: Using the Posterize option on your image allows you to change the color brightness range from 2 to the full 255. When you set the levels at a low range, you reduce the number of colors used in the image, giving the colors a banded look. l Threshold: Using the Threshold option changes your file into a true black and white image—not grayscale. The dialog box contains a slider that allows you to set the Threshold level. Every color above that brightness level is changed to white, and every color below that level becomes black. Although it doesn’t make your image look very good, it is ideal for finding the brightest and darkest values of your image. This helps you choose settings for many of the other adjustments. l Gradient Map: A Gradient Map takes a gradient and uses the lowest tones of the gradient to replace the darkest tones of your file and the highest tones to replace the lightest and everything in between. l Selective Color: This option allows you to change the level of colors individually. Choose from nine color options in the drop-down menu, and change the CYMK sliders to adjust that color. When you click any one of these Adjustment icons, an adjustment layer is created above the selected layer in your Layers panel, and the Adjustment panel changes to display the settings for that adjustment, as shown in Figure 12.3. To edit any one of your adjustment layers, select it in the Layers panel and the settings reappear in the Adjustment panel, allowing you to adjust them. FIGURE 12.3 Clicking the Levels adjustment icon in the Adjustment panel created a Levels adjustment layer and opened the Levels settings in the Adjustment panel. 19_584743-ch12.indd 37519_584743-ch12.indd 375 5/3/10 10:33 AM5/3/10 10:33 AM Part IV: Enhancing, Correcting, and Retouching 376 Adjustment panel icons When an adjustment is displayed in the Adjustment panel, new icons appear on the bottom of the Adjustment panel, as shown in Figure 12.4. You can reset the adjustment to defaults, toggle the visibility, or return to the Adjustment list to add a new adjustment. FIGURE 12.4 New icons appear in the Adjustment panel when an adjustment is being added. Return to adjustment list Adjustment affects all layers below or clip to layer Toggle layer visibility View previous state Reset to defaults You also can choose to clip the adjustment to the layer below it. Generally, when you add a layer to the Layers panel, it affects all the layers below it, but if you want your adjustment to affect only 19_584743-ch12.indd 37619_584743-ch12.indd 376 5/3/10 10:33 AM5/3/10 10:33 AM Chapter 12: Adjustment Workflow 377 the layer below, you can click this icon. You know if your adjustment layers are clipped to the layer below them because they look like the layers in Figure 12.5, with an arrow added to the adjustment layer pointing to the layer below. The layer that is being affected by the adjustment has an underlined name. FIGURE 12.5 An adjustment layer that has been clipped to the layer below it does not affect any other layer. Adjustment presets The center area of the Adjustments panel is full of adjustment presets that you can use or add to create quick fixes for images that are similar in lighting or color. For instance, if you have several photos of the same model under the same lighting, you could adjust the color curves to perfection in the first image, save those settings as a preset, and then apply them to subsequent images. To save a preset, change your settings and click the Adjustment panel menu icon to display the Adjustment panel menu, as shown in Figure 12.6. Choose Save Preset, and give your preset an eas- ily identifiable name. To access the presets, click the appropriate adjustment setting and select a default preset or one of your own from the preset list, as shown in Figure 12.7. 19_584743-ch12.indd 37719_584743-ch12.indd 377 5/3/10 10:33 AM5/3/10 10:33 AM Part IV: Enhancing, Correcting, and Retouching 378 FIGURE 12.6 Save a preset using the Adjustments panel menu. FIGURE 12.7 Access your presets as well as the defaults from the Adjustment list panel. 19_584743-ch12.indd 37819_584743-ch12.indd 378 5/3/10 10:33 AM5/3/10 10:33 AM Chapter 12: Adjustment Workflow 379 Summary This chapter introduced you to the workflow you should use when applying adjustments, correc- tions, and artistic effects to your image. It also introduced you to the auto adjustments and the Adjustment panel, so you will know how these elements work as you use them in coming chapters. I covered these topics: l Workflow organization l Making auto adjustments l Using the Adjustment panel 19_584743-ch12.indd 37919_584743-ch12.indd 379 5/3/10 10:33 AM5/3/10 10:33 AM 19_584743-ch12.indd 38019_584743-ch12.indd 380 5/3/10 10:33 AM5/3/10 10:33 AM . the image by making the tones on the dark side 50 percent darker and the tones on the light side lighter. l Levels: You can adjust the levels of the brightness values in your file by adding. changes every color to 255 minus its original value. l Posterize: Using the Posterize option on your image allows you to change the color brightness range from 2 to the full 255. When you set the. adjustment panel 19_584743-ch12.indd 37319_584743-ch12.indd 373 5/3/10 10:33 AM5/3/10 10:33 AM Part IV: Enhancing, Correcting, and Retouching 374 Tip If you are correcting photos often, you probably