Distorting for Fun 539 Corbis Digital Stock Figure 2-6: Use the Straighten tool to fix the horizon line in the Lens Correction dialog box. Zigzag in Glass in Book VII Pond Ripples mode Normal Wave Frosted mode Spherize Chapter 2 Applying Filters for Special Occasions Figure 2-7: A normal clock takes on Dali-esque qualities with various Distort filters. 540 Pumping Up the Noise The Glass filter can do the following to your images: ✓ Add a glass-block texture ✓ Add a canvas texture ✓ Create frosted-glass fuzziness ✓ Break up your image with tiny lenses Don’t like any of Photoshop’s textures? No biggie; you can also load your own texture. Click the Texture pop-up menu (the right-pointing arrow) and select Load Texture. Pumping Up the Noise Noise in images consists of any graininess or texture that occurs, either because of the inherent quality of the image or through the editing process. Noise filters, such as the Photoshop Add Noise plug-in, produce random texture and grain in an image. If you’re new to image editing, you might wonder why you’d want to add noise to an image in the first place. Wouldn’t it be smarter to remove it? Well, sometimes. In practice, you can find a lot of applications, including the following, that call for a little noise here and there: ✓ Adding texture: Objects that become too smooth, either because of blurring or other image editing you may have done, often look better when you add some noise to give them a texture. This technique is par- ticularly useful if one object in an image has been edited, smoothed, or blurred more than the other objects in the image. ✓ Blending foreign objects into a scene: When you drop a new object into the middle of an existing scene, the amount of grain or noise in the new object is often quite different from the objects it’s joining. For example, say you’ve decided to take a photo of your house and want to insert a certain luxury car in your driveway. Unfortunately, your digi- tal photo of your brother-in-law’s luxo-mobile is a lot sharper than the picture of your house. Adding a little noise can help the two objects blend more realistically. You may even forget that the car isn’t yours. ✓ Improving image quality: Images that contain smooth gradients often don’t print well because some printers can’t reproduce the subtle blend of colors from one hue to another. The result is objectionable banding in your printed image: You can see distinct stripes where the colors prog- ress from one to another. Adding a little noise can break up the gradient enough that your printer can reproduce the blend of colors, and the noise/grain itself is virtually invisible on the printed sheet. Pumping Down the Noise 541 Pumping Down the Noise Although the Add Noise filter adds grain, the other filters in the Noise sub- menu don’t add noise at all; instead, they make noise and artifacts (flaws, such as the dust and scratches on old film) less noticeable. Choose Filter➪ Noise to find your tools, which include ✓ Despeckle: This filter makes dust spots in your image less noticeable by decreasing the contrast of your entire image — except at the edges. That translates into a slightly blurry image (which masks the spots) that still retains sharpness along the edges of image components. You end up with a little blur to soften the image but enough detail in the edges that the picture still looks good. ✓ Dust & Scratches: This filter concentrates its blurring effect on only those areas of your image that contain scratches and other artifacts. Photoshop performs this magic by looking at each pixel in an image and moving out in a radial direction until it encounters an abrupt transition in tone. (That’s a signal that a spot or scratch has been found.) You can specify the radius in which Photoshop searches for the little culprits, from 1 to 100 pixels. Be careful not to overdo it. Too much of this filter can obliter- ate the detail in the image. Leave the Threshold at 0. If you journey into the world of mush, try using Edit➪Fade right after you apply the filter. Book VII When working with any of the Noise filters, be very conservative at first. Chapter 2 All the Noise filters involve destruction of image data. Remember, that’s just the nature of filters, in general — changing pixel data. A little bit can Applying Filters for Special Occasions help — and be just the effect you’re looking for. Just a little bit more, however, may completely wreck things. ✓ Median: This filter reduces contrast around dust motes, thus hiding them, in a slightly different way. This filter looks at the pixels surround- ing each pixel in the image and replaces the center one with a new pixel that has the median brightness level of that group. The process is a little hard to describe succinctly, but basically, the bright spots darken while the rest of the image isn’t affected. For more on the Median filter, see Book VII, Chapter 1. ✓ Reduce Noise: This filter, shown in Figure 2-8, is designed to remove luminance noise and JPEG artifacts that can appear on digital photos. Luminance noise is grayscale noise that makes images look overly grainy. Here’s some info on the options: • Strength: Specify the amount of noise reduction. You can reduce noise in the overall image or (if you click the Advanced button) chan- nel by channel. Be sure to check out the Blue channel, in particular. It’s often the channel that captures all the crud. • Preserve Details: A higher number preserves edges and details but reduces the amount of noise removal. Find a happy medium. 542 Breaking Your Image into Pieces • Reduce Color Noise: Removes random colored pixel artifacts. • Sharpen Details: Counteracts the fact that removing noise reduces sharpness, as well. • Remove JPEG Artifact: Check this option to remove the annoying blocks and halos that can occur because of low-quality JPEG compression. You can also save and reload your settings. Click the disk/arrow icon. In the New Filter Settings dialog box, enter a name for your settings and click OK. To load your settings, choose your desired settings from the Settings drop-down list. Figure 2-8: The Reduce Noise filter attempts to remove noise while retaining some sharpness in edges and details. Breaking Your Image into Pieces The Pixelate filters in Photoshop break your images into bits and pieces, providing more of those painterly effects you can get with brush strokes and artistic filters. The Pixelate submenu includes the Crystallize filter (applied to the little girl shown in Figure 2-9), as well as plug-ins that produce color halftone effects, fragmented images, and the pointillize effect (used in the “Creating Snow and Rain” Putting It Together project, in this chapter). Rendering 543 Corbis Digital Stock Book VII Figure 2-9: The Crystallize filter breaks your image into polygonal shapes. Chapter 2 Applying Filters for Special Occasions Rendering In computerese, rendering means creating something from nothing, in a way. That’s why all rendering filters in Photoshop produce special effects by cre- ating a look, object, or lighting effect that’s melded with your original image. Using the Clouds filter The Clouds filter can muster a sky full of clouds from scratch with a few clicks of the mouse, as in the now-cloudy picture shown in Figure 2-10. This filter creates clouds using random values from the foreground and background colors. Indeed, most Photoshop veterans use this filter so much that they have a sur- prising number of clouds in their images. Find it at Filter➪Render➪Clouds. To create a more contrasty cloud effect, hold down Alt (Option on the Mac) quickly when choosing the command. If you don’t like the first set of clouds you get, apply the filter again and again until you do. If you want a more “realistic” sky, try using a dark sky blue for your foreground color and a very light blue, or white, color for your background color. Be sure to apply the filter on its own layer, if you don’t want to obliterate the original contents of your image. 544 Rendering Brand X Pictures Figure 2-10: Got clouds? Make your own with the Clouds filter. Need a quick Web background image? Create a 128-x-128-pixel (or some mul- tiple of that size) image and apply the Clouds filter. It tiles seamlessly on your Web page. Creating fibers This filter can create a textilelike effect out of thin air. Choose Filter➪ Render➪Fibers. In the dialog box that appears, move the Variance slider to increase the contrast between light and dark areas. Move the Strength slider to increase the tightness of the weave of the fibers. Click the Randomize button to get another variation of the effect of the filter. Using other rendering filters Other useful filters on the Render submenu (at Filter➪Render) include Rendering 545 ✓ Difference Clouds: Use this filter to create puffy objects in the sky (or foggy clouds at lower levels). Instead of performing this magical feat the way the Clouds filter does, the Difference Clouds filter uses image infor- mation to figure the difference in pixel values between the new clouds and the image they’re joining. The result is a unique cloud effect. Try applying the filter repeatedly to create a marbleized effect. ✓ Lens Flare: This filter creates the reflection effect that plagues photogra- phers when they point their cameras toward a strong light source, such as the sun. Photoshop mimics several different kinds of photographic lenses, giving you useful flares that can spice up concert photos, add a sunset where none existed, and create other kinds of lighting bursts. In the Lens Flare dialog box, specify a location for the center of the flare by clicking the image thumbnail or dragging the crosshair. ✓ Lighting Effects: As a sort of photo-studio lighting setup, this filter uses pixels to do its work. You can set up 16 different lights and manipulate how they illuminate your photo. Putting It Together Creating Snow and Rain Sometimes, you may come across a photo that needs a little bit of atmosphere thrown in Book VII to give it extra punch. And I mean atmosphere literally. By using a couple of ﬁlters and Chapter 2 a blend mode, you can add some rain or snow to any image. Just follow these steps to Applying Filters for Special Occasions create either rain or snow: 1. Open a color image. If it isn’t currently in RGB mode, choose Image➪Mode➪ RGB Color. Make sure you’re in RGB mode; the blend mode used in these steps doesn’t work correctly with CMYK images. 2. Drag the background layer to the Create a new layer icon at the bottom of the Layers panel. You now see a layer named Background Copy in the Layers panel. 3. Double-click the name Background Copy and type Snow. This isn’t a mandatory step. I’m just being ultra-organized. continued 546 Rendering continued 4. First, set your background color to white. With the Snow layer active, choose Filter➪Pixelate➪Pointillize. In the dialog box, set your cell size to whatever value you prefer. Click OK. The bigger the cell size, the bigger the snowflakes or raindrops. For rain, you might try a cell size of 3 (which is the minimum) or 4. For snow, try a larger cell size, between 6 and 9. I used a value of 7 in my image. 5. On the Snow layer, choose Image➪Adjustments➪Threshold. Move the slider all the way to the right, to a max value of 255. This adjustment takes the colored cells and turns them to either black or white. By using a value of 255, all brightness values less than 255 turn black, and the remaining value turns white. 6. On the Snow layer, select Screen from the Mode pop-up menu in the Layers panel. The Screen blend mode lightens the Snow layer, where it mixes with the background. Blending with black pixels has no effect; therefore, they drop out, as shown in the figure. 7. Choose Filter➪Blur➪Motion Blur. In the dialog box that opens, specify the Angle and Distance values. If you want the wind to appear to be blowing hard, set the angle more diag- onally, around 45 degrees. If you want the precipitation to appear to be coming straight down, set the angle to 90 degrees. Setting the distance elon- gates the pointillized cells that you created in Step 4, making them look a little more realistic. For snow, start with a range of about 8 to 12 pixels. For rain, start a little higher, around 15 to 25 pixels. I used a value of 12 pixels in my figure. Getting Organic with the Sketch Filters 547 If you’re creating rain, proceed to Step 8. If you’re a snow person, you’re done, as shown in the figure. 8. Choose Filter➪Sharpen➪Unsharp Mask. The Unsharp Mask dialog box appears. 9. Specify the Amount, Radius, and Threshold values and click OK. The Unsharp Mask filter gives the illusion of sharpening the focus of the image by increasing the contrast between the pixels. I used an amount of 500%, a Radius of 1, and kept the Threshold at 0. This gives the raindrops a little more definition. 10. Choose Filter➪Blur➪Motion Blur. In the dialog box that appears, specify the Angle and Distance values. Again, the angle is up to you, but make it consistent with the value that you used in Step 7. Set the distance according to how you want your rain to appear — a moderate spring rain or a torrential, close-to-hurricane type of downpour. In the image shown here, I used 45 degrees and 25 pixels. Book VII Chapter 2 Applying Filters for Special Occasions Getting Organic with the Sketch Filters The Sketch filter submenu contains a few filters that don’t really belong there. That’s because many current Photoshop filters were acquired from Aldus Corporation (now defunct), and Adobe had to shoehorn them into the organizational structure of Photoshop. But no matter — they work nonetheless. If you were to encounter a picture of Michelangelo’s David, shown in Figure 2-11, you might be tempted to sketch the famous sculpture by using one of the filters you can find when you choose Filter➪Sketch. Perhaps a Conté Crayon effect or a Graphic Pen and Ink look would be nice. But the Sketch submenu also includes other artistic effects, such as the Note Paper look, a halftone screen, chalk and charcoal, and even a bas-relief effect that turns flat images into a Michelangelo-esque sculpture. 548 Getting Organic with the Sketch Filters Normal Conté Crayon Graphic pen Note Paper Corbis Digital Stock Figure 2-11: Give your digital photos a more organic feel with the Sketch filters. You can also experiment with these other Sketch filters: ✓ Chrome: Creates a polished chrome effect. Use the Levels adjustment to add more contrast, if necessary. ✓ Photocopy: Gives that infamous, anachronistic look (dating back to the days when photocopiers didn’t do a very good job of reproducing half- tone images). Creates areas of black and white with little gray value when the default foreground and background colors of black and white are selected.