Rasterize: Vectors That Act Like Pixels


Illustrator has a Rasterize command in the Object menu that gives you the ability to rasterize any object in Illustrator. The Rasterize effect in the Effect menu gives you the exact same functionalitybut as a Live Effect. When you think about it, the result of applying this effect is a bit of an oxymoron: the object is a vector, yet it appears and acts like a raster image.

To apply the Rasterize effect, select an object and choose Effect > Rasterize. The options that appear in the Rasterize dialog are similar to those found in the Document Raster Effects Settings dialog and you can even choose to have the Rasterize dialog pick up the resolution settings from that dialog by selected the Use Document Raster Effects Resolution radio button (Figure 7.74).

Figure 7.74. To ensure a consistent overall appearance, you might want to have the Rasterize effect share the same resolution setting as in the Document Raster Effects Settings dialog.


There are several reasons why you might want to use the Rasterize effect. For example, you might want to disable anti-aliasing on small text so that it appears easier to read when displayed on a Web site (more information on this can be found in Chapter 10). In addition, you can use the Rasterize effect to change the Color Model of selected artwork (see the following "What If . . . You Apply the Rasterize Effect to a Raster Image?" example).

What If . . . You Apply the Rasterize Effect to a Raster Image?

It doesn't take a whole lot to realize that the Rasterize effect can turn vector elements into raster elements, but have you ever thought about the possibility of applying the Rasterize effect to a placed raster image in Illustrator? Not only is it possible, it's extremely useful as well. Besides the obvious ability to temporarily downsample high-resolution files to a lower resolution for faster processing, the Rasterize effect has the ability to change color modes. That means you can place a full color photo into a layout, but use the Rasterize effect to change the image to grayscale. Of course, since it's a Live Effect, you can always switch it back to color at any time.

In addition, you can use this method of converting images to grayscale for when you want to convert an entire file to grayscaleincluding both raster and vector objects. In such a case, you may find it easier to apply the Rasterize effect at the layer level, where all items on a layer can be converted to grayscale.




Real World Adobe Illustrator CS2
Real World Adobe Illustrator CS2
ISBN: 0321337026
EAN: 2147483647
Year: 2003
Pages: 147
Authors: Mordy Golding

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