Fundamentals: Resampling in Photoshop

Excerpted from Real World Adobe Photoshop CS5 for Photographers (Peachpit Press)

By Conrad Chavez

One of the most important issues in working with images—and, unfortunately, one that few people seem to understand—is how the resolution can change relative to (or independent of) the physical size of your image. There are two ways you can change resolution: scaling and resampling. The illustration below is an example of simple scaling—it doesn’t change the pixel dimensions, just the resolution.

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