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Professional Information Technology-Programming Book part 26 doc

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brightness. For example, sometimes I want to make the skin tones just a little lighter or find that it would be better if the sky were a bit darker. Please keep in mind that right now, I'm only talking about brightness areas that are predominant in a large part of the image and don't have to be isolated by masking. Masked channels come later in the workflow. In case you don't already know, adjusting the contrast curve for a given range of brightness is easy: 1. Open the Curves dialog, press the Cmd/Ctrl key and the cursor will become an eyedropper. Click on the tone in the image that is the midtone in the brightness range that you want to adjust. A black dot will appear at precisely that brightness location along the Curve line. 2. Repeat the process for any other brightness tones you want to change. 3. Select each Curve line dot one at a time. For each dot, press the Up arrow key to brighten that tone or the Down arrow key to darken it. Press the Left/Right arrow keys to move that point to a different position along the curve. If necessary, you can isolate the changes you are making to include only a given brightness range by placing double points above and below the curve point that you are moving. Figure 6-9 shows an image and its curve after changing the brightness and contrast of the midtones in the shadows to bring out a bit more detail. Figure 6-9. An image and its curve after changing the brightness and contrast of the midtones in the shadows to bring out a bit more detail. The same Curves adjustment layer can be used to change the color tint of a particular range of brightness. Figure 6-10 shows the before and after of a portrait in which there is a tint reflecting from a nearby wall. This is something you couldn't do in Camera Raw, so doing it now is your only chance. You could use the Color Balance adjustment for this job, but you'd have to make selections to target the tinted area, so you couldn't apply the same layer to a series of images. This adjustment is particularly useful if the shadows or highlights are picking up the reflection of a nearby colored object, for example, a wall or sweater. Follow these steps: Figure 6-10. The before and after of a portrait in which there is a tint reflecting from a nearby wall that needed correction. See the orange highlight on the camera- left ear, top of the sweater, and on the highlighted rim of her face? There may also be times when you want to increase a tint for atmospheric effect. 1. Press Cmd/Ctrl-click in the image on an area that contains the brightness level you had in mind. 2. Place two anchor points on either side of the anchor point dot you just placed, leaving enough space between them so that your change "blends" with surrounding areas of brightness. 3. Go to the color channel most likely to make the change in tint. Raise the target anchor dot to intensify the primary color for that channel. Lower it to intensify the complementary color for that channel. You may need to use two channels to get or remove exactly the intended shadow tint. 6.2.3. Color Balance Although the most accurate way to set color balance is to use a gray or color card with the Levels command (see "Levels Adjustment" earlier in this chapter), the Color Balance dialog is an excellent way to set color balance subjectively. For instance, suppose you shoot a landscape before sunset and the color balance doesn't feel right to you, so you use the Levels approach. Well, maybe it's better but still doesn't have a strong enough sunset feeling. Figure 6-11 shows the before and after of this scene. Figure 6-11. A landscape shot just before sunset that looks more like it was shot at 3 p.m. (left) until you "correct" it with the Color Balance adjustment layer (right). Getting the subjective look I want is simply a matter of dragging sliders until I like what I see. Always start by correcting the color that most needs correction. Drag toward the name of that color to intensify the color or toward the name of the complementary color to diminish the influence of the primary color. The secret here (as it is for most adjustments) is to be sure the Preview box is checked. The settings that gave me the sunset feeling are shown in the Color Balance dialog in Figure 6-12. Figure 6-12. The settings for creating an orange sunset feeling. You could use the same method to warm or cool the atmosphere of any image. NOTE Many users prefer the Adjustments Variations command instead of the Color Balance command because they can see the effect before the adjustment and can see several comparisons at once. However, until Adobe makes Variations work as an adjustment layer, the only way you can apply the command nondestructively is to create a copy of a flattened version of your file. To do that, highlight all the layers, then press Cmd/Ctrl-+ Opt/Alt-E. A new merged layer will appear and you can use the Variations command on that. Of course, you've added quite a bit more file size, and you can't try another Variation without repeating the whole process. 6.2.3.1. Hue/Saturation The Hue/Saturation adjustment layer is most useful for two categories: hue and saturation (duh?). Seriously, most of the time you'll use both of the dialog's sliders regardless of what your purpose isyou'll just use them differently. But I haven't yet told you what the two purposes are, have I? NOTE There is a script from Fred Miranda called Velvia Vision that gives you a number of versatile options for creating truly beautiful and authentic photos that feature highly saturated colors. Since this script costs a mere $25 and lets you preview the result before you apply it, I suggest you check it out (www.fredmiranda.com). There's more on Fred Miranda in Chapter 11. Assuming your original image wasn't a JPEG, you might wonder why you'd want to change the saturation of colors in the image when you already had a chance to do it nondestructively in Camera Raw. Well, first, I suggest you only do it in Camera Raw when your camera or shooting conditions have simply dulled colors to a point beyond the norm. If you're doing it to stylize the image, you'll find it much easier to do different interpretations in Photoshop. You may even want to do these in a variety of Layer Comps (see Chapter 9) so you can present different interpretations to the client within the same file. Pumped up saturation can give your image the look of fantasy or romance. Take a look at the before and after images in Figure 6-13 to see what I mean to romanticize the image. Figure 6-13. The image on the left would be considered a nice photo; the image on the right is saturated (with a lens blur effect added during the Effects processes described in Chapter 10). Here's how the Hue/Saturation command was used to enhance the image in Figure 6-13: 1. In this instance, the image needed some adjustments with the Levels and Curves layers to bring up more detail in the darker areas of the picture and add color to the sky. So I raised the Curve in the darker shadows and lowered it in the top third of the highlights. 2. I clicked the Adjustment Layer icon and chose Hue/Saturation. When the dialog opened, I moved the Hue slider to +5 to favor the greens in foliage. Then I dragged the Saturation slider to +36. 6.2.3.2. Brightness/Contrast The Brightness/Contrast adjustment layer can be useful for quick and dirty lightening, darkening, or contrast. It generally works best when you want to burn or dodge a small area of the image or the outside of a vignette by first masking a targeted area of the image. For other applications, it is much better (and less destructive) to employ the controls in Levels and Curves. I don't like the old-fashioned elliptical vignettes much, unless I am intentionally dating the picture. Generally, I vignette to force the viewer to focus attention on central parts of the imaging by darkening peripheral stuff that could be distracting. To vignette an image: 1. Use the freehand Lasso tool to draw a loose loop around the edges of the image, as shown in Figure 6-14. Figure 6-14. A freehand selection drawn to vignette less important areas on the outside of the image. 2. Feather the selection as much as necessary and then invert it. Make sure you keep the selection active. 3. Select Brightness/Contrast from the Adjustment Layers menu at the bottom of the Layers palette. The adjustment layer will appear. Be sure to move it above the Levels and Curves layers you've already created. Also, this is going to be a regional adjustment, so you may want to put it into a Regional Adjustments Group should you create more of same. 4. Drag the Brightness slider to darken the vignette as much as you like. You can also play with the Contrast slider. I often flattened the darkened part of the image to make it even less obtrusive. 6.2.3.3. Channel Mixer The Channel Mixer has two primary uses: creating bizarre color effects and making stunning monochrome images (see the "Monochrome Effects" section in Chapter 10). Figure 6-15 shows you the difference between simply desaturating the image and using the Channel Mixer with the Monochrome box checked to mix colors in channels for the black and white tonalities that work best for a particular image. Figure 6-15. On the left, a color image after using the Desaturate command; the image on the right is after the Channel Mixer is used. 6.2.3.4. Photo Filter The Photo Filter adjustment layer's name is a bit confusing. First of all, it's not found on the Filters menu. Second, its job is to emulate the glass filters used over the lens in traditional color photography. You can control the intensity of the effect by dragging the density slider. The filters that are emulated are: 85, LBA, 81, 80, LBB, and 82. You can also choose many straightcolor overlay effects. You could achieve the latter with a combination of solid color layers and blending modes, but the Photo Filter adjustment layer is quicker and more interactive. Figure 6-16 shows the difference between an image that has simply been desaturated and one created with the Channel Mixer. Figure 6-16. A color image as first opened (left) and after treatment with the Photo Filter's 85 filter (right). 6.2.3.5. Solid Color The only difference between this adjustment layer and simply filling an empty layer with any color from the color picker is that a Solid Color adjustment layer will let you change your mind by simply presenting you with the Color Picker dialog. A Solid Color adjustment layer, in conjunction with Blend Modes, opens all sorts of possibilities for special colorization and semi-toning effects. Using a solid layer on a black and white image creates an image "toned" in the solid color. In Figure 6-17 shows the result of using a solid color layer on a color image. In this case, the Solid Color adjustment layer was used with the Overlay Blend Mode at about 40 percent opacity. For more on using this technique, see "Changing an Object's Color" in Chapter 8. Figure 6-17. The original color image (left) and the same image "toned" with a Solid Color adjustment layer in Overlay Blend Mode at 38 percent fill. 6.2.3.6. Selective Color This is an amazing way to create color effects in a color image. You do it by mixing the primary CMYK colors (even though you're working with an RGB image) as they affect one color at a time. Figure 6-18 shows you the difference for just one such adjustment. The possibilities are literally infinite. Figure 6-18. The original color image (left) and the same image(right) after using the Selective Color adjustment layer in one of an infinite number of combinations. 6.2.3.7. Threshold Threshold divides the image into pure black and white. You can choose the luminosity value that makes the dividing line. This is a very easy way to make a selection that is darker or lighter than the Select Color Range command. Besides, it's interactive, so you can see what you're doing. You can then make a mask or selection from the result. You can fine tune that mask by painting on it or by modifying it in Quick Mask mode. You can also smooth the selection and then convert it to a pen path. Or you could stroke the selection to create particular edges. Another trick is to cut and paste the result of the Threshold adjustment into a mask channel and then use the Gaussian Blur filter and selections to feather the mask in varying degrees. See Figure 6-19 for a before and after example of adding details to highlights and shadows using this technique. Figure 6-19. Specific areas of highlights and shadows were lightened and darkened by making masks with the Threshold filter. NOTE You could use the Threshold adjustment layer to make corrections to the highlights and shadows that are nondestructive and readjustable. Make one mask for extreme highlights and another for extreme shadows. Then use each to mask a Levels adjustment layer. The highlights and shadows in Figure 6-19 can be readjusted and have an editable mask 6.2.3.8. Gradient This is a terrific function for creating bizarre color effects. I find that these effects can be extremely useful for making backgrounds for poster and album cover photos of entertainers. I'm sure you can find a million other reasons for using them (see Figure 6-20). Figure 6-20. The original image (left) and the same image with a gradient map used as a background for a glamour photo (right). You can use any gradient in Photoshop's Gradients directory or any gradient that you make or modify and then save. The gradient automatically maps itself to brightness values and colors in the target image. If the gradient is monochrome, you get a monochrome image. 6.2.3.9. Pattern The Pattern function is pretty cool when you need to quickly create a textured background layer or when you need a pattern to use for creating a texture. Since patterns are often made to be seamless, you can easily make them small or large. They're also cool as backgrounds because they can be lit with the Lighting Effects filter (boy, would I love Adobe if they made that an adjustment layer), vignetted, blended with a gradient, or have shadows on them. You could also use the warp tool or project them onto a 3D shape to make them more credible as object surfaces. It would take a whole book to go into all the possibilities, but suffice it to say that Pattern can be a surprisingly versatile and helpful tool. You can see the result of using it and the Lighting Effects filter in Figure 6-21. Figure 6-21. A pattern layer (left) and result of using it as a background in conjunction with the Lighting Effects filter (right). 6.2.3.10. Invert The Invert function reverses the tones in the image from positive to negative, as shown in Figure 6-22. Figure 6-22. A positive black and white image and its negative. 6.2.3.11. Posterize The Posterize function reduces the image to a number of colors specified in the resulting dialog box. Figure 6-23 shows an example of an image that has been reduced from full color to eight colors. Figure 6-23. A photo before and after posterization. . mind that right now, I'm only talking about brightness areas that are predominant in a large part of the image and don't have to be isolated by masking. Masked channels come later in. a bit more detail. The same Curves adjustment layer can be used to change the color tint of a particular range of brightness. Figure 6-10 shows the before and after of a portrait in which there. tinted area, so you couldn't apply the same layer to a series of images. This adjustment is particularly useful if the shadows or highlights are picking up the reflection of a nearby colored

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