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Distort Filters

Distort filters run the gamut from gentle glassiness to image-destroying twirls and even more. Want to make your picture look like it's going down the drain, melting, or being blown off the page? These are the filters for you. In this section, you'll try filters on the picture of a box of anchor chain shown in Figure 16.1 and in the color plate section.

Diffuse Glow

Not all the Distort filters actually distort. The Diffuse Glow filter adds a gentle haze of the background color over the lighter areas of a picture. This creates a glow that blends into the image. Hard to say why it is in the Distort family of filters, but it is cool, nevertheless.

The controls are Graininess, Glow Amount, and Clear Amount. Try to balance the Glow Amount and Clear Amount. For soft glows, I suggest that you keep the Graininess setting low. Higher numbers increase the graininess. This might be useful if you want a somewhat speckled look. In Figure 16.2, I used white as a background color, with Graininess of 9 and Glow Amount of 7 to place a glow on the chain. Using white as the glow color puts a soft foggy glow on the subject. Additional grain would make it look more like the beginning of a snowstorm.

Also, when you have a picture like this one, with limited color, you can often get a nice effect by increasing the saturation of the whole picture, either before or after you apply the glow. High saturation (90100%) will really make the colors stand up and shout.

Displace

The Displace filter is one of several Photoshop filters that requires the use of a displacement map, which works like a texture map, placing the image over a grid that creates a textured look. You can find a collection of these in the Photoshop Plug-Ins folder. Set the amount, in a percentage, for horizontal and vertical displacement in the dialog box. Higher percentages have a greater effect. After you set the amount of displacement, you're asked to choose a displacement map from the collection in the Plug-Ins folder inside the Photoshop folder. Figure 16.3 shows a partial list of maps, and Figure 16.4 shows the results of applying the Crumbles map. The effect you get from this filter depends on which map you choose. You need to try them to see their effects because the names aren't necessarily helpful and the previews don't look much like the resulting effects.

Displacement maps are images or patterns that are saved in the Photoshop format and applied as part of a mathematical formula that moves each pixel in the original image according to the values in the displacement map. You can actually use any Photoshop image as a displacement map. Just choose it instead of one of the default files.

Glass and Ocean Ripple

I decided to lump the discussion of these two filters together because of the similar effects they can have on an image. They both create displacements that make the image seem as if you are looking through glass or water.

The Glass filter offers you a greater amount of control (see Figure 16.5). You can select a type of texture, such as Frosted, Tiny Lens, or Canvas, and you also can load a texture of your own. Just choose Load Texture from the pop-up menu at the bottom of the dialog box.

Use the Smoothness slider to increase the fluidity of the image. Keeping the Distortion low and the Smoothness high will create a subtle effect. Try the opposite for a much more distorted image. The scaling slider adjusts the scale of the distortion from 50%200%.

The Invert button at the bottom of the dialog box replaces the light areas of the texture with dark areas, and vice versa. Figure 16.6 shows the results of applying the Glass filter.

The Ocean Ripple filter is quite similar. It creates an effect that makes your image appear as though it is under water. It is an effective filter and easier to use than the Glass filter because it has only two options on its dialog box.

Pinch, Spherize, and ZigZag

The Pinch, Spherize, and ZigZag filters are lumped together, not so much because they do the same thing but because their interfaces are so similar. Figure 16.7 shows the dialog box for the ZigZag filter.

Keep an eye on the grid provided at the bottom of the box as you drag the Amount slider higher or lower. It can give you a good indication (as can the preview area) of what is going on in the image. See the final version in Figure 16.8. It turned the chain into a pool of melted iron.

This is a tough filter to master, but a good one to have in your bag of tricks. The Spherize filter can be very useful on occasion, but don't try to force it. If it doesn't look right, you can try Liquify to create a similar "bubble" effect. Also, you can set a negative amount using the Amount slider to generate a hollow instead of a bump. And if this doesn't satisfy your needs, try the Pinch or ZigZag filters.

Shear

You can tell a great deal about most filters just by their names, but this isn't one of themunless you're an engineer. The Shear filter warps images horizontally. (It moves them in relation to the vertical line.) Drag the line in the Shear dialog box, as shown in Figure 16.9. Watch the preview to see the effect of shearing the picture. You also can add more control points on the curve by clicking it at different areas. These control points are like joints; they enable you to redirect the motion of the curve.

Figure 16.10 shows the results of the Shear filter. I've set the image to Repeat Edge Pixels, so it now looks as if the warping left a smudge of pixels behind.

One Way The Shear filter works in only one direction. If you want something to shear vertically instead of horizontally, simply rotate the image before you apply the filter. Then rotate it back again.

Twirl

The Twirl filter does precisely what its name suggests: It spins an image. You can control the amount of spin with the slider within the dialog box. This is a great filter for creating special effects. So far, I haven't found very many subtle uses for the Twirl filter, but if you can, go to it. It creates wonderful, kaleidoscopic effects and can also simulate a swirling drain. It looks great with the chains, as shown in Figure 16.11.