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494 Part III ✦ Selections, Masks, and Filters 5. Choose Filter ➪ Pixelate➪ Crystallize. Enter a moderate value in the Cell Size option box. I opted for the value 12, just slightly larger than the default value. After pressing Enter, you get something along the lines of the selection outline shown in the right image in Figure 11-2. The filter refracts the softened edges, as if you were viewing them through textured glass. 6. Switch back to the marching ants mode. Then use the selection as desired. I merely pressed Ctrl+Backspace to fill the selection with white, as shown in the top-left image in Figure 11-3. Figure 11-3: Which aura will Moses don today? The images illustrate the effects of applying each of four filters to a heavily feathered selection in the quick mask mode and pressing Ctrl+Backspace. Crystallize Facet MosaicPointillize 495 Chapter 11 ✦ Full-Court Filtering You may find this technique particularly useful for combining images. You can copy the selection and paste it against a different background or copy a background from a different image and choose Edit ➪ Paste Into to paste it inside the crystal halo’s selection outline. Figure 11-3 shows several variations on the Crystal Halo effect. To create the upper- right image, I substituted Filter ➪ Pixelate ➪ Facet for Filter ➪ Pixelate ➪ Crystallize in Step 5. I also sharpened the result to increase the effect of the filter (which never- theless remains subtle). To create the lower-right image, I applied the Mosaic filter in place of Crystallize, using a Cell Size value of 8. Finally, to create the lower-left image, I applied the Pointillize filter. Because Pointillize creates gaps in a selection, I had to paint inside Moses to fill in the gaps and isolate the halo effect to the back- ground before returning to the marching ants mode. Creating a mezzotint A mezzotint is a special halftone pattern that replaces dots with a random pattern of swirling lines and wormholes. Photoshop’s Mezzotint filter is an attempt to emu- late this effect. Although not entirely successful — true mezzotinting options can be properly implemented only as PostScript printing functions, not as filtering func- tions —they do lend themselves to some pretty interesting interpretations. The filter itself is straightforward. You choose Filter ➪ Pixelate ➪ Mezzotint, select an effect from the Type submenu, and press Enter. A preview box enables you to see what each of the ten Type options looks like. Figure 11-4 shows off four of the effects at 230 ppi. To create Figure 11-5, I applied the Mezzotint filter set to the Long Lines effect. Then I used the Edit ➪ Fade Mezzotint command to mix filtered and original images. I selected Overlay from the Mode pop-up menu and set the Opacity value to 40 per- cent. The result is a scraped image. (I’ve decreased the resolution of the image to 180 ppi so that you can see the effect a little more clearly.) When applied to grayscale artwork, the Mezzotint filter always results in a black- and-white image. When applied to a color image, the filter automatically applies the selected effect independently to each of the color channels. Although all pixels in each channel are changed to either black or white, you can see a total of eight col- ors —black, red, green, blue, yellow, cyan, magenta, and white— in the RGB com- posite view. The upper-left example of Color Plate 11-3 shows an image subject to the Mezzotint filter in the RGB mode. If the Mezzotint filter affects each channel independently, it follows that the color mode in which you work dramatically affects the performance of the filter. For example, if you apply Mezzotint in the Lab mode, you again whittle the colors down to eight, but a very different eight — black, cyan, magenta, green, red, two muddy blues, and a muddy rose— as shown in the top-middle example of Color Plate 11-3. If you’re looking for bright happy colors, don’t apply Mezzotint in the Lab mode. 496 Part III ✦ Selections, Masks, and Filters Figure 11-4: The results of applying the Mezzotint filter set to each of four representative effects. These line patterns are on par with the halftoning options offered when you select Mode ➪ Bitmap, as discussed back in Chapter 4. Medium dots Coarse dots Short lines Long lines 497 Chapter 11 ✦ Full-Court Filtering Figure 11-5: To get this effect, I applied the Mezzotint filter and then chose the Fade command (on the Edit menu in Photoshop 6). In the Fade dialog box, I selected the Overlay mode and set the Opacity value to 40 percent. In CMYK, the filter produces roughly the same eight colors that you get in RGB — white, cyan, magenta, yellow, violet-blue, red, deep green, and black. However, as shown in the top-right example of the color plate, the distribution of the colors is much different. The image appears much lighter and more colorful than its RGB counterpart. This happens because the filter has a lot of black to work with in the RGB mode but very little— just that in the black channel —in the CMYK mode. The bottom row of Color Plate 11-3 shows the effects of the Mezzotint filter after using the Fade command to mix it with the original image. As in Figure 11-4, I chose Overlay from the Mode pop-up menu and set the Opacity value to 40 percent. These three very different images were all created using the same filter set to the same effect. The only difference is color mode. 498 Part III ✦ Selections, Masks, and Filters Edge-Enhancement Filters The Filter ➪ Stylize submenu offers access to a triad of filters that enhance the edges in an image. The most popular of these is undoubtedly Emboss, which adds dimension to an image by making it look as if it were carved in relief. The other two, Find Edges and Trace Contour, are less commonly applied but every bit as capable and deserving of your attention. Embossing an image The Emboss filter works by searching for high-contrast edges (just like the Sharpen Edge and High Pass filters), highlighting the edges with black or white pixels, and then coloring the low-contrast portions with medium gray. When you choose Filter ➪ Stylize ➪ Emboss, Photoshop displays the Emboss dialog box shown in Figure 11-6. The dialog box offers three options: ✦ Angle: The value in this option box determines the angle at which Photoshop lights the image in relief. For example, if you enter a value of 90 degrees, you light the relief from the bottom straight upward. The white pixels therefore appear on the bottom sides of the edges, and the black pixels appear on the top sides. Figure 11-7 shows eight reliefs lit from different angles. I positioned the images so that they appear lit from a single source. Figure 11-6: The Emboss dialog box lets you control the depth of the filtered image and the angle from which it is lit. 499 Chapter 11 ✦ Full-Court Filtering Figure 11-7: Reliefs lit from eight different angles, in 45-degree increments. In all cases, the central sun image indicates the location of the light source. Height and Amount values of 1 pixel and 250 percent were used for all images. ✦ Height: The Emboss filter accomplishes its highlighting effect by displacing one copy of an image relative to another. Using the Height option, you specify the distance between the copies, which can vary from 1 to 10 pixels. Lower values produce crisp effects, as demonstrated in Figure 11-8. Values above 3 goop up things pretty good unless you also enter a high Amount value. Together, the Height and Amount values determine the depth of the image in relief. The Height value is analogous to the Radius value in the Unsharp Mask dialog box. You should therefore set the value according to the resolution of your image —1 for 150 ppi, 2 for 300 ppi, and so on. Tip 135 90 45 180 0 –135 –90 –45 500 Part III ✦ Selections, Masks, and Filters Figure 11-8: Examples of different Height settings (first value) and Amount settings (second value). The Angle value used for each image was 135 degrees. ✦ Amount: Enter a value between 1 and 500 percent to determine the amount of black and white assigned to pixels along the edges. Values of 50 percent and lower produce almost entirely gray images, as you can see in the top row of Figure 11-8. Higher values produce sharper edges, as if the relief were carved more deeply. As a stand-alone effect, Emboss is only so-so. It’s one of those filters that makes you gasp with delight the first time you see it but never quite lends itself to any practi- cal application after you become acquainted with Photoshop. But if you think of Emboss as an extension of the High Pass filter, it takes on new meaning. You can use 3, 200% 1, 50% 3, 50% 5, 50% 1, 200% 5, 200% 1, 500% 3, 500% 5, 500% 501 Chapter 11 ✦ Full-Court Filtering it to edit selection outlines in the quick mask mode, just as you might use the High Pass filter. You also can use it to draw out detail in an image. Figure 11-9 shows the result of using the Fade command immediately after applying the Emboss filter. (Remember, Fade now resides on the Edit menu, not the Filter menu.) First, I applied the Emboss filter at an Angle of 135 degrees, a Height of 2 pix- els, and an Amount of 250 percent. Then I pressed Ctrl+Shift+F to display the Fade dialog box. To create the left example, I selected Darken from the Mode pop-up menu. This added shadows to the edges of the image, thus boosting the texture without unduly upsetting the original brightness values. I selected the Lighten blend mode to create the right example. In both cases, I set the Opacity value to 70 percent. Figure 11-9: After applying the Emboss filter, I used my old friend the Fade command to darken (left) and lighten (right) the image. To create a color relief effect, apply the Emboss filter and then select the Luminosity option in the Fade dialog box. This retains the colors from the original image while applying the lightness and darkness of the pixels from the filtered selection. The effect looks something like an inked lithographic plate, with steel grays and vivid colors mixing together. An example of this effect at 80 percent Opacity appears in the first example of Color Plate 11-4. The second example in that same color plate shows a more impressive —if less practical —technique. Rather than applying Luminosity, I chose the Difference mode inside the Fade dialog box. With its hard edges and vivid colors, this image looks like some impossible frame from an educational film on genetic engineering. I can just hear the narrator commenting, “Prom dates have changed dramatically since scientists discovered how to splice the red rose with the poppy.” Tip 502 Part III ✦ Selections, Masks, and Filters Tracing around edges Photoshop provides three filters that trace around pixels in your image and accen- tuate the edges. All three filters live on the Filter➪ Stylize submenu: ✦ Find Edges: This filter detects edges similarly to High Pass. Low-contrast areas become white, medium-contrast edges become gray, and high-contrast edges become black, as in the labeled image in Figure 11-10. Hard edges become thin lines; soft edges become fat ones. The result is a thick, organic outline that you can overlay onto an image to give it a waxy appearance. To achieve the bottom-left effect in the figure, I chose Edit ➪ Fade Find Edges and applied the Overlay mode and an 80 percent Opacity setting. She’ll never get her hand off that canning jar as long as she lives. ✦ Glowing Edges: This Gallery Effects filter is a variation on Find Edges, with two important differences: Glowing Edges produces an inverted effect, chang- ing low-contrast areas to black and edges to white, as in the middle image in Figure 11-10. This filter also enables you to adjust the width, brightness, and smoothness of the traced edges. Glowing Edges is a great backup command. If you aren’t satisfied with the effect produced by the Find Edges filter, choose Glowing Edges instead and adjust the options as desired. If you want black lines against a white background, press Ctrl+I to invert the effect. ✦ Trace Contour: Illustrated on the right side of Figure 11-10, Trace Contour is a little more involved than the others and slightly less interesting. The filter traces a series of single-pixel lines along the border between light and dark pix- els. Choosing the filter displays a dialog box containing three options: Level, Upper, and Lower. The Level value indicates the lightness value above which pixels are considered to be light and below which they are dark. For example, if you enter 128 —medium gray, the default setting— Trace Contour draws a line at every spot where an area of color lighter than medium gray meets an area of color darker than medium gray. The Upper and Lower options tell the filter where to position the line— inside the lighter color’s territory (Upper) or inside the space occupied by the darker color (Lower). Like Mezzotint, Trace Contour applies itself to each color channel independently and renders each channel as a 1-bit image. A collection of black lines surrounds the areas of color in each channel; the RGB, Lab, or CMYK composite view shows these lines in the colors associated with the channels. When you work in RGB, a cyan line indicates a black line in the red channel (no red plus full-intensity green and blue becomes cyan). A yellow line indicates a black line in the blue channel, and so on. You get a single black line when working in the grayscale mode. 503 Chapter 11 ✦ Full-Court Filtering Figure 11-10: The top row of images demonstrates the effect of the three edge-tracing commands available from the Filter ➪ Stylize submenu. After applying each command, I used the Fade command to apply the blend modes and Opacity values demonstrated in the bottom row. Creating a metallic coating The edge-tracing filters are especially fun to use in combination with Edit➪ Fade. I became interested in playing with these filters after trying out the Chrome filter included with the first Gallery Effects collection. Now included with Photoshop as Filter ➪ Sketch ➪ Chrome, this filter turns an image into a melted pile of metallic goo. No matter how you apply Chrome, it completely wipes out your image and leaves a ton of jagged color transitions in its wake. It’s really only useful with color images, and then only if you follow up with the Fade command and the Luminosity mode. Even then, I’ve never been particularly satisfied with the results. Find Edges Glowing Edges Trace ContourTrace Contour Overlay, 80% Overlay, 60% Multiply, 100% [...]... Figure 11- 16 Enter a positive value from 1 to 999 degrees to spiral the image in a clockwise direction Enter a negative value to spiral the image in a counterclockwise direction As you are probably already aware, 360 degrees make a full circle, so the maximum 999-degree value equates to a spiral that circles around almost three times, as shown in the bottom-right example in Figure 11-17 Figure 11- 16: The... you can’t create using Photoshop s gradient tool 509 510 Part III ✦ Selections, Masks, and Filters Twirling spirals The Twirl filter rotates the center of a selection while leaving the sides fixed in place The result is a spiral of colors that looks for all the world as if you poured the image into a blender set to a very slow speed When you choose Filter ➪ Distort ➪ Twirl, Photoshop displays the Twirl... face ✦ Combine creatively: Don’t expect a single distortion to achieve the desired effect If one application isn’t enough, apply the filter again Experiment with combining different distortions Photoshop Caution 6 Distortion filters interpolate between pixels to create their fantastic effects This means the quality of your filtered images depends on the setting of the Interpolation option in the General... in the top-left box in Figure 11-19 4 Choose the Twirl filter and apply it at – 360 degrees so that the spiral moves counterclockwise To create the top-right image in the figure, I applied the Twirl filter three times Each repetition of the filter adds another ring of ripples 5 Press Ctrl+J to copy the selection to a layer 6 Choose Edit ➪ Transform ➪ Flip Horizontal 7 Lower the Opacity value to 50 percent... a pond ripple effect 515 5 16 Part III ✦ Selections, Masks, and Filters Pond Ripples Ridges = 5 10 20 Ridges = 5 10 20 Ridges = 5 10 20 Out From Center Around Center Figure 11-22: The effects of the ZigZag filter using three Ridges values and each of the three Style pop-up menu settings In all cases, the Amount value was 20 ✦ Out From Center: When you select this option, Photoshop moves pixels outward... sophisticated, but they’re also relatively easy to apply The fourth filter, Wave, affords you greater control, but its options are among the most complex Photoshop has to offer The Ripple filter To use the Ripple filter, choose Filter ➪ Distort ➪ Ripple Photoshop displays the Ripple dialog box shown in Figure 11-23 You have the following options: ✦ Amount: Enter an amount between negative and positive... Motion Blur Enter 90 degrees in the Angle option and use 20 pixels for the Distance option This blurs the image vertically to soften the blast lines, as in Figure 11-35 6 Choose Filter ➪ Distort ➪ Wave Then enter the values shown in Figure 11- 36 in the Wave dialog box Most of these values are approximate; experiment with other settings if you like The only essential value is 1 percent in the Vert option... zigzags, check out the Ripple and Wave filters, described in the next section (The ZigZag filter creates ripples and the Ripple filter creates zigzags Go figure.) When you choose Filter ➪ Distort ➪ ZigZag, Photoshop displays the ZigZag dialog box, shown in Figure 11-20 The dialog box offers the following options: ✦ Amount: Enter an amount between negative and positive 100 in whole-number increments to specify... images Pinch wraps an image on a rounded cone; Spherize wraps onto a sphere Chapter 11 ✦ Full-Court Filtering Tip Both filters can affect elliptical regions only If a selection outline is not elliptical, Photoshop applies the filter to the largest ellipse that fits inside the selection As a result, the filter may leave behind a noticeable elliptical boundary between the affected and unaffected portions... produces what I would term a zigzag effect The last rows of Figures 11-21 and 11-22 show the effects of the Around Center option Chapter 11 ✦ Full-Court Filtering Creating parallel ripples and waves Photoshop provides four means to distort an image in parallel waves, as if the image were lying on the bottom of a shimmering or undulating pool Of the four, the ripple filters — which include Ripple, . Stylize ➪ Emboss, Photoshop displays the Emboss dialog box shown in Figure 11 -6. The dialog box offers three options: ✦ Angle: The value in this option box determines the angle at which Photoshop lights. Vertical Only options from the Mode pop-up menu at the bottom of the Spherize dialog box. 6 Photoshop 6 Caution 508 Part III ✦ Selections, Masks, and Filters Figure 11-13: Constantine does the. effect, I applied the Mezzotint filter and then chose the Fade command (on the Edit menu in Photoshop 6) . In the Fade dialog box, I selected the Overlay mode and set the Opacity value to 40 percent. In