Most of the Photoshop filters are housed conveniently under one roof in the Filter Gallery dialog. All the Photoshop filters are available for RGB files, most of the filters are available for Grayscale files, fewer are available for CMYK Color, Lab Color, and 16-bits-per-channel files, still fewer are available for 32-bits-per-channel files, and none are available for Bitmap and Indexed Color files. If you try to select a filter and discover that it’s not available, the likely cause is that it’s incompatible with the current document color mode or bit depth.
If you apply a filter to a Smart Object, it becomes an editable, removable Smart Filter (see pages 344–345). A small handful of them, such as Clouds and Blur, are applied in one step simply by choosing the filter name from a submenu on the Filter menu. Most of the Photoshop filters are applied either via the Filter Gallery or via an individual dialog. You can apply filters to a whole layer or just to a selection on a layer.
(To locate tasks in which we use individual filters, see “Filter menu” in the index.) Applying filters Using this chapter, you will learn techniques for applying filters, including using the Filter Gallery and Smart Filters, and use filters to make a photo look like an oil painting or tinted drawing.