Adobe 13101332 User Guide - Page 324

Adobe Photoshop Help Using Help | Contents | Index Applying Filters for Special Effects Back 324 Apply filters to individual channels You can apply a filter to an individual channel, apply a different effect to each color channel, or apply the same filter but with different settings. Create backgrounds By applying effects to solid-color or grayscale shapes, you can generate a variety of backgrounds and textures. You might then blur these textures. Although some filters have little or no visible effect when applied to solid colors (for example, Glass), others produce interesting effects.You might try Add Noise, Chalk & Charcoal, Clouds, Conté Crayon, Craquelure, Difference Clouds, Glass, Grain, Graphic Pen, Halftone Pattern, Mezzotint, Mosaic Tiles, Note Paper, Patchwork, Pointillize, Reticulation, Rough Pastels, Sponge, Stained Glass, Texture Fill, Texturizer, and Underpainting. Combine multiple effects with masks or with duplicate images Using masks to create selection areas gives you more control over transitions from one effect to another. For example, you can filter the selection created with a mask. You can also use the history brush tool to paint a filter effect onto part of the image. First, apply the filter to an entire image. Next, step back in the History palette to the image state before the filter was applied, and set the history brush source to the filtered state. Then, paint the image. (See "Reverting to a previous version of an image" on page 38.) Improve image quality and consistency You can disguise faults, alter or enhance, or make a series of images look related by applying the same effect to each. Use the Actions palette to record the process of modifying one image, and then use this action on the other images. (See "Using the Actions palette" on page 484.) Improving performance with filters Some filter effects can be memory intensive, especially when applied to a high-resolution image.You can use these techniques to improve performance: • Try out filters and settings on a small portion of an image. • Apply the effect to individual channels-for example, to each RGB channel-if the image is large and you're having problems with insufficient memory. (With some filters, effects vary if applied to the individual channel rather than the composite channel, especially if the filter randomly modifies pixels.) • Free up memory before running the filter by using the Purge command. (See "Correcting mistakes" on page 37.) • Allocate more RAM to Photoshop. If necessary, exit from other applications to make more memory available to Photoshop. • Try changing settings to improve the speed of memory-intensive filters, such as Lighting Effects, Cutout, Stained Glass, Chrome, Ripple, Spatter, Sprayed Strokes, and Glass filters. (For example, with the Stained Glass filter, increase cell size. With the Cutout filter, increase Edge Simplicity, or decrease Edge Fidelity, or both.) • If you plan to print to a grayscale printer, convert a copy of the image to grayscale before applying filters. However, applying a filter to a color image and then converting to grayscale may not have the same effect as applying the filter to a grayscale version of the image. Using Help | Contents | Index Back 324