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316 Chapter 9 Enhancements and Masking Figure 9.19 Top text layer set to Normal mode. Figure 9.20 Top text layer set to Multiply mode. This is a simple way to make text or graphics “overprint” on the underlying image instead of covering it up (Fig- ures 9.19 and 9.20). You can also use it anytime you have scanned text or other graphics that you’d like to print on something else. The main problem is areas that are not completely white. Any area that is darker than white will darken the under- lying image, so you’ll occasionally need to choose Image > Adjustments > Levels and move the upper-right slider to make sure that the background is pure white. As an example, let’s take the tattoo from Figure 9.21 and put it on Figure 9.22. We place the tattoo on a layer above the second image, setting the blending mode of that layer to Multiply (Figure 9.23), choose Image > Adjustments > Desaturate, and then adjust the image using Levels until only the tattoo appears and the background surrounding it disappears (Figure 9.24). Figure 9.22 Image to which the tattoo will be applied. (©Stockbyte, www.stockbyte.com.) Figure 9.23 Result of setting the tattoo layer to Multiply mode. Figure 9.24 Result of desaturating and then adjusting the image with Levels. Figure 9.21 This tattoo will be trans- planted to another image. (©Stockbyte, www.stockbyte.com.) If some areas don’t disappear, eradicate them with the Eraser tool. 317 IV: Creative Techniques Earlier chapters talked about how both your screen and printer simulate a wide range of colors using only red, green, and blue light; or cyan, magenta, and yellow ink. To demonstrate this, we could create an image containing three circles, one per layer: cyan, magenta, and yellow. But they don’t act like ink when they overlap (Figure 9.25). So we simply set the blending mode for each layer to Multiply, and then everything works the way it should (Figure 9.26). Now let’s use Multiply to create a contour drawing out of a photograph (Figure 9.27). Because we’re going to end up with black lines and no color information, choose Image > Mode > Grayscale. To get contours, choose Filter > Stylize > Trace Contour, and move the slider around a bit (Figure 9.28). Trace Contour puts a black line around the edge of a particular shade of gray. But there are two prob- lems: The contours aren’t usually smooth, and there’s only one contour for the entire image. To fi x the fi rst problem, smooth out the image by applying the Gaussian Blur or the Median fi lter. The latter requires a little more effort, and that’s where we can start putting the Multiply blending mode to work. Figure 9.27 A photograph converted to a contour drawing. (©2008 Dan Ablan.) Figure 9.25 In Normal mode, the three circles don’t interact with each other. Figure 9.26 Result of setting each layer to Multiply mode. Figure 9.28 The Trace Contour dialog. 318 Chapter 9 Enhancements and Masking Duplicate the layer enough times so that you have one layer for each contour that you want. Then apply the Trace Contour fi lter to each layer, using a different level setting each time in the Trace Contour dialog. Each layer now contains a different contour (Figure 9.29). To combine those images into one, set the blending mode of each layer to Multiply so they print on top of each other, which will make the white areas disappear (Figure 9.30). Figure 9.30 Result of combining all the layers in Multiply mode. Here’s another way of using blending modes with fi lters. Let’s say you’ve opened an image and then chosen Filter > Stylize > Find Edges. Now you have a bunch of black lines representing the edges of all the objects that were in the photo (Figure 9.31). But what if you wanted those black lines to print on top of the original image? Immediately after applying the fi lter, choose Edit > Fade Find Edges and set the blending mode to Multiply. Photoshop applies the fi ltered image to the original as if you had printed on top of it (Figure 9.32). If you want six contours, for example, press Command/Ctrl-J five times to end up with six layers total. Figure 9.29 All the layers that are needed to create the drawing. 319 IV: Creative Techniques Figure 9.31 Result of applying the Find Edges filter. (©2008 Dan Ablan.) Figure 9.32 Result of fading the edges in Multiply mode. Multiply mode is used quite a bit in Photoshop’s layer styles, which can be confusing when you’re trying to do something unusual. Say you have some black text on a deep blue background, and you want to add a drop shadow. With the text layer active, choose Layer > Layer Style > Drop Shadow. But a black drop shadow with dark text makes the text hard to see (Figure 9.33), so you decide to change the shadow color to white. The shadow disappears! That’s because its mode is automatically set to Multiply (in the Layer Style dialog), and white disap- pears in Multiply mode. To get things to work the way you wanted, change the mode to Normal (Figure 9.34). Color Burn Mode Color Burn mode isn’t easy to describe or understand, but can be very useful nonetheless. As with all the darken blending modes, white doesn’t do anything in Color Burn mode. Black leaves any red, green, or blue numbers that are 255 alone, forcing all others to zero. When you paint with a primary color (pure red, green, or blue), you’ll end up with the amount of that primary color that was in the underlying image—and nothing else. When you paint with a color that’s made out of two primaries, Photoshop strips the third primary color out of the underlying image. Here’s where the goodies come in. Paint with shades of gray to darken and intensify the colors that are in the underlying image. This can work wonders for darkening bland-looking skies, making them more colorful while at Figure 9.33 The black drop shadow doesn’t contribute to the legibility of the text. Figure 9.34 A white shadow isn’t possible in Multiply mode, so the mode has been changed to Normal. You can use Color Burn mode to colorize grayscale images. Be sure to change the mode of the image from grayscale to RGB or CMYK. Lower the opacity of your painting tool; otherwise, you’ll end up with a rather dark result. 320 Chapter 9 Enhancements and Masking the same time maintaining the bright white clouds (Figures 9.35 and 9.36). Shadows can look good using Color Burn. If a shadow is falling on a textured background, more of the texture will come through, because it will maintain more of the highlights (Figures 9.37 and 9.38). Figure 9.37 Shadow applied in Multiply mode. Figure 9.38 Shadow applied in Color Burn mode. Linear Burn Mode Linear Burn mode acts much like Multiply mode but has a greater tendency to make areas pure black. It main- tains more of the color from the underlying image. Use it anytime you’d think about using Multiply mode but want a higher-contrast result. If standard shadows (which usually use Multiply mode) look a little too gray, try Linear Burn; you might like the result better (Figures 9.39 and 9.40), although you’ll need to lower the Opacity setting to avoid getting an overly dark result. Figure 9.39 Shadow applied in Multiply mode, with Opacity reduced. (Compare the result to Figure 9.37.) Figure 9.40 Shadow applied in Linear Burn mode. Figure 9.35 The original image. (©2008 Dan Ablan.) Figure 9.36 Result of painting with gray across the sky in Color Burn mode. 321 IV: Creative Techniques Lighten Blending Modes Each of the darken blending modes (Darken, Multiply, Color Burn, and Linear Burn) has an equally useful opposite mode. With all the lighten blending modes, black simply disappears, and anything brighter than black has the potential to brighten the underlying image. Lighten Mode Lighten mode compares the active layer to the underly- ing image and allows the areas of the active layer to show up that are brighter than the underlying image. But it looks at the red, green, and blue components of the image separately, which makes for some unpredictable results. Lighten mode can be a lifesaver when working with trans- parent surfaces, such as those of a 3D render. The only problem with combining a multiple-pass render with glass is to get both to show up at once (Figures 9.41 and 9.42). With both images loaded into Photoshop, one atop the other, set the blending mode of the top layer to Lighten, and—bingo, the render comes together (Figure 9.43). Figure 9.41 Image with bulb visible. (©2008 Luxology.com.) Figure 9.42 Image with filament visible. Figure 9.43 Result of combining the two images in Lighten mode. Try Lighten mode when experimenting with fi lters. For instance, choosing Filter > Stylize > Glowing Edges cre- ates bright lines where the edges of an object were in an image (Figure 9.44). Use this fi lter to add extra interest to an image by choosing Edit > Fade Glowing Edges, and then setting the blending mode to Lighten immediately after applying the fi lter (Figure 9.45). You get the bright edge effect while maintaining the overall look of the original image. 322 Chapter 9 Enhancements and Masking Figure 9.44 The colors shift when the Glowing Edges filter is applied. (©2008 Dan Ablan.) Figure 9.45 More of the original image is visible after Lighten mode is used. The same concept works great when you’re using the Lighting Effects fi lter, which usually brightens or darkens an image. In Lighten mode, you can force that fi lter to brighten only (Figures 9.46 and 9.47). Use it after applying the Blur fi lter, to add a soft-focus look (Figure 9.48). Figure 9.46 The original image. (©2008 Dan Ablan.) Figure 9.47 The Lighting Effects filter brightens and darkens the image. Figure 9.48 Result of fading the Light- ing Effects filter in Lighten mode. Lighten mode can be wonder- ful when sharpening an image. Duplicate the layer twice, set the top layer to Lighten and the middle layer to Darken, and then sharpen the top two layers. Then you can control the dark and bright halos separately by lowering the opacity of each of those two layers. 323 IV: Creative Techniques Screen Mode If Multiply mode acts like ink, Screen mode is its opposite, acting like light instead. In this mode, black simply disap- pears, whereas anything brighter than black brightens the underlying image. Screen mode is useful when an image has a black background with anything that resembles light within it. Use it with things like sparklers and lightning; put the sparkler on a layer above another image, set the layer mode to Screen, choose Image > Adjustments > Levels, and pull the upper-left slider in until the background of the sparkler disappears (Figures 9.49 and 9.50). Figure 9.49 Result of using Normal mode to combine images on two layers. (©2008 Dan Ablan.) Figure 9.50 Result of applying Screen mode to the top layer. The black disappears. Screen mode is used in many of Photoshop’s layer styles. Say you want to add a glow around some text by choosing Layer > Layer Style > Outer Glow. That technique works fi ne as long as you choose a bright color like white or yellow, but doesn’t look good if you use a dark color like navy blue (Figure 9.51). Because Photoshop uses Screen mode as the default method for applying the glow to the underlying image, shining a dark blue light at something isn’t going to change it much. To remedy the situation, change the blending mode to either Normal or Multiply (Figure 9.52). 324 Chapter 9 Enhancements and Masking Figure 9.51 Dark Outer Glow on text won’t be very visible in Screen Mode Figure 9.52 Changing the blending mode to Multiply allows the Outer Glow to be visible. Remember the overlapping circles from Figures 9.25 and 9.26? There we were thinking ink (Multiply mode). Sup- pose we want circles of light instead? By setting each of the layers to Screen mode, you can get the circles in Figure 9.53 to interact with each other as if they were circles of light (Figure 9.54). Color Dodge Mode Color Dodge mode usually brightens the underlying image while at the same time making the colors more saturated. It’s very useful because it doesn’t change the darkest part of the image very much, which allows you to brighten an area while still maintaining good contrast. Use the Paint- brush tool and paint with a dark shade of gray on a layer set to Color Dodge mode (Figures 9.55 and 9.56). It’s use- ful for adding more interest to otherwise dull-looking hair. (Photographers often use a separate light source to add highlights to hair.) Use Color Dodge mode as a replace- ment for Screen mode when you’re adding an Outer Glow layer style to text (Figures 9.57 and 9.58). Figure 9.55 The original image. (©2008 Dan Ablan.) Figure 9.56 The water was brightened with gray paint in Color Dodge mode. Figure 9.53 In Normal mode, the three circles don’t interact with each other. Figure 9.54 Result of switching each layer to Screen mode. 325 IV: Creative Techniques Figure 9.57 Yellow glow created in Screen mode. (©2008 Dan Ablan.) Figure 9.58 The same yellow glow created in Color Dodge mode. Figure 9.59 The same yellow glow from the earlier figures, this time cre- ated in Linear Dodge mode. Linear Dodge Mode Linear Dodge mode works much like Screen mode, but has a greater tendency to make areas pure white. Use it any time you’re considering Screen mode but want a higher- contrast result (Figure 9.59). Contrast Blending Modes The majority of blending modes on the next section of the menu combine the ideas used as examples in the darken and lighten blending modes. In all of these modes, 50% gray simply disappears, and anything darker than 50% has the potential of darkening the underlying image, whereas areas brighter than 50% have the potential to brighten the underlying image. In essence, these modes increase the contrast of the underlying image by brightening one area while darkening another. Overlay Mode In Overlay mode, the information on the underlying image is used to brighten or darken the active layer. Any areas darker than 50% gray will act like ink (or Multiply mode), whereas any areas brighter than 50% gray will act like light (or Screen mode). Overlay mode is use- ful when you want to add color to the underlying image [...]... crisp-edged objects that have a noticeable difference in color or brightness from the surrounding background With this tool, you have to paint around the edges of objects to tell Photoshop which areas should be deleted, and Photoshop will try to figure out what should be kept Blending sliders: A quick-and-dirty way to isolate objects that are radically different in brightness from their surroundings... click and drag the Background Eraser on the image, Photoshop watches the color under the crosshair and deletes everything within the circle that’s similar to that color (Figure 9.104) Trace near the edge of the object you want to keep It’s okay if the circular part of the cursor overlaps the subject Just don’t let the crosshair hit the subject; otherwise, Photoshop will start to delete that area as well... Foreground Color check box Sampling Figure 9.109 The Sampling icons from left to right: Continuous, Once, Background Swatch 340 If Photoshop is forcing you to be overly precise with your mouse movements, use the Sampling icons (Figure 9.109) The default Continuous setting causes Photoshop to watch the color under the crosshair as you’re moving your mouse (Figures 9.110 and 9.111) That setting works great... for the Background Eraser tool Tolerance Settings Getting the right Tolerance setting on the options bar is essential to using the Background Eraser tool successfully This setting determines how much Photoshop will be able to stray from the color under the crosshair If the background is very similar to the subject in brightness or color, use a low Tolerance setting If the background is quite different... attempting to delete On occasion, the Tolerance setting may not be enough to isolate the subject from the background (Figure 9.107) In that case, use the Protect Foreground Color check box on the options bar Photoshop deletes the color under the crosshair and keeps the foreground color (Figure 9.108) While the Background Eraser tool is active, you can hold down Option/Alt and click the part of the image you... gradient map 333 Chapter 9 Enhancements and Masking Hue/Saturation/Brightness Blending Modes The final set of modes divides the colors of an image into three components: hue, saturation, and brightness Photoshop applies only one or two of these qualities to the underlying image These are wonderfully helpful modes, with practical and obvious uses Hue Mode Figure 9.89 Changing the color of an image by... you’re moving your mouse (Figures 9.110 and 9.111) That setting works great with images that have multicolored backgrounds If the image’s background doesn’t vary much in color, try the Once setting to make Photoshop pay attention to only the color under the crosshair at the exact moment that you click It won’t stray from that color, so you can click the background and then paint back and forth across the . after applying the fi lter, choose Edit > Fade Find Edges and set the blending mode to Multiply. Photoshop applies the fi ltered image to the original as if you had printed on top of it (Figure. Ablan.) Figure 9.32 Result of fading the edges in Multiply mode. Multiply mode is used quite a bit in Photoshop s layer styles, which can be confusing when you’re trying to do something unusual. Say. underlying image—and nothing else. When you paint with a color that’s made out of two primaries, Photoshop strips the third primary color out of the underlying image. Here’s where the goodies

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