Using Photoshop Filters

You have tons of different types of filters to choose from. Photoshop has 13 different categories and roughly 100 filters that do things like sharpening and blurring your image, adding brush strokes, distorting, creating textures, and creating other effects. The simplest filter to understand and use is one that’s not even found in the Filter menu: The Invert filter, a single-step filter, isn’t in the Filter menu because, technically, it really isn’t a filter, but it illustrates nicely what filters do to your images. (Find it at Image-->Adjustments-->Invert.)

When you apply Invert to an image, Photoshop examines each pixel and immediately flips it to its opposite in tone and color. A black pixel becomes a white pixel, a dark gray pixel becomes a light gray pixel, and a dark red pixel becomes a light cyan pixel. While this filter flips grayscale pixels to their exact opposite, if you want to turn a color negative into a positive, you have to do some manual adjusting after the inversion.

Actually, you can use many other filters to do much the same thing. Based on the information in your image, pixels are lightened, darkened, changed in color, or moved around from place to place as the filter changes contrast, blurs, sharpens, corrects color, or distorts your image. Some other filters, ignore image information, but they change pixels in similar ways based on their own internal rules.