Adobe Photoshop CS5 : Maximizing Filters - Filters Defined & Preparing to Use Filters

Filters are among Photoshop’s most popular features. These specialized add-ons can be used to boost productivity or add special effects. Photoshop ships with over 100 built-in filters, and there is a rich array of others available from third-party developers. Filters are so popular that you’ll find more tutorials online than you could ever make it through in a lifetime.

Photoshop almost did not ship with filters, because many at Adobe thought they were too “gimmicky.” However, John Knoll, co-creator of Photoshop, managed to “sneak” them in. Those early execs were partially right, though: When used improperly (or too often), filters can be gimmicky. Think of filters like spices: When used properly, they can add to a meal, but if they’re overused, they can ruin it—and no one can live on spices alone.

Both built-in and third-party filters were run on this image. You would not normally run as many filters on a single image, but you can see just how diverse filters can be.

Filters Defined

The proper use of filters can significantly extend Photoshop’s capabilities. There are filters that perform important image-enhancement tasks for removing grain or damage. Additionally, filters can be used for tasks like blurring and sharpening image details.

Filters allow you to achieve more quickly what otherwise would be time-consuming results; they can even unlock options that could not be done with built-in tools. Filters can often create stylized looks as well as enhance the lighting of a photo.

By definition, a filter must reside in Photoshop’s Plug-ins folder. Besides the bundled filters that are installed with Photoshop, you’ll find a few specialty filters on the Photoshop installer DVD or in the Support area of Adobe’s Web site.

Preparing to Use Filters

Filters can save time and in fact can even be fun to use. Before you rush in and try out every filter in Photoshop, you need to make sure the image is ready to be processed. Many filters are render intensive, so there’s no reason to spend extra time on pixels you will be throwing away.

Fix Major Errors

Filtering mistakes only draws further attention to them. Most important, make sure the image is properly exposed. This can easily be accomplished using a Levels adjustment (Image > Adjustments > Levels). .”

Set Your View

Filtering an image is easiest when you can see all your pixels (otherwise, resampling occurs). For best results, zoom in 100% or choose View > Actual Pixels. You can also double-click on the magnifying glass in the Tools panel or press Command+Option+0 (Ctrl+Alt+0). The Navigator panel is useful to get a global overview and to move quickly around an image that is zoomed in.

Check the Color Mode

You’ll want to be sure that you are working in RGB mode whenever possible (Image > Mode > RGB). This will ensure that you have the most filters available. Very few filters work in CMYK mode because CMYK conversion is supposed to be the last step in processing an image. Only those filters that are meant for print work have been optimized to work in CMYK mode.

If you have a CMYK image and you need to convert it back to RGB mode for filtering, go ahead. You do not have to worry about color shift when converting from CMYK to RGB. Because CMYK has fewer colors than RGB, no information will be lost.

Check the Bit Depth

It’s also important to keep an eye on bit depth when working with filters, or your filter options will be limited. The vast majority of filters only run on images in the 8-bit mode. In fact, as of Photoshop CS5, only 37 of the built-in Photoshop filters will work in 16-bit mode and only 20 of them work in 32-bit mode.

The filters designed to work at higher bit depths are designed primarily for image enhancement (as opposed to stylization). These filters are targeted for use with digital photography applications. While a 16-bit image can be processed more without showing banding or posterization, you may need to work in 8-bit mode. If you can work in 16-bit mode, do so, but be prepared to lose some functionality with filters and image adjustments. If a filter is grayed out, it doesn’t work in the selected bit depth.