Proper application of filters significantly extends the abilities of Photoshop. It is possible to achieve results quickly that are time consuming (or even impossible) otherwise. When buying filters, be sure to check compatibility. Make sure that the filters readers buy are compatible with their operating system and version of Photoshop. The Lens Blur filter adds a very needed depth of field blur to Photoshop. The Brush Stroke filters could have simply been named Artistic Filters Part II. The Distort filters allow you to bend, push, squish, and completely reshape the user's photo. Noise filters can create textures or grain. The Add Noise filter introduces random noise to the image. The Reduce Noise filter can be used for noise reduction as well as for smoothing out the Joint Photographic Experts Group artifacts. The sharpen filters can be used to focus soft images by increasing the contrast of adjacent pixels.