Applying Filters

One of Photoshop's trademarks is the capability to quickly change the appearance of a photograph or an image. Not only does Photoshop ship with a laundry list of filters for this purpose, but you also can buy other third-party filters for even more specialized purposes. Here we discuss some of the more widely used filters.

Did you Know?

If you notice that most of Photoshop's filters are grayed out, there's a good chance your document is set to grayscale or CMYK. In reality, many of Photoshop's filters will work only in RGB documents. This is specifically because those filters use calculations that can be applied only in RGB. If you need to use one of these filters in a CMYK document, choose Image, Mode, RGB to switch color modes, apply the filter, and then choose Image, Mode, CMYK to go back to your original color space. Be aware that color shift might (and most likely will) occur.

Vanishing Point

Every so often, a feature comes along that is so amazing, it just blows your mind. Vanishing Point, found in the Filter menu, is one of those features (see Figure 5.115).

Figure 5.115. Choosing Vanishing Point from the Filter menu.

The Vanishing Point filter enables you to perform a variety of Photoshop functions in perspective. By defining a series of vanishing points, you can easily establish what Photoshop calls planes, which determine how your edits are applied to your image.

Did you Know?

It's always best to create a new empty layer before using Vanishing Point. In this way, your results are always put into the blank layer, keeping your original image intact.

When the Vanishing Point dialog box is open, you begin by first defining a plane. Using the Create Plane tool, click on four corners to define the plane you want to work with (see Figure 5.116). You can press the X key on your keyboard to temporarily zoom in while you're defining your plane to make it easier to align it correctly. After you've clicked on the fourth corner, Photoshop creates a plane that can be used for editing (see Figure 5.117). If you copied some art onto the Clipboard before opening Vanishing Point, you can paste it right into the dialog box (see Figure 5.118). As you drag the pasted image or art onto the plane, Vanishing Point automatically adjusts it to the correct perspective (see Figure 5.119). Pretty cool, eh?

Figure 5.116. Starting to define the four corners of the Vanishing Point plane.

Figure 5.117. The completed plane.

Figure 5.118. Pasting an image into Vanishing Point.

Figure 5.119. Positioning the art onto the plane.

It gets better. With Vanishing Point, you aren't limited to just one plane. You can extend planes to create a complete world of perspective and use tools such as the Clone Stamp tool to perform cloning in perspective. Start by opening an image and creating a new layer. Then open Vanishing Point and set up your first plane (see Figure 5.120). When you have a plane created, press the Command (Ctrl) key and drag out a new plane from the edge of your existing plane (see Figure 5.121). Adjust the plane so that it is in the correct perspective (see Figure 5.122). You can drag out additional planes as necessary. When you drag one plane from another, it keeps the planes all in perspective to each other. You can then use any of the editing tools listed along the left side of the Vanishing Point dialog box to perform edits in perspective (see Figure 5.123).

Figure 5.120. Creating the first Vanishing Point plane.

Figure 5.121. Starting to drag out a new plane from an existing one.

Figure 5.122. Adjusting the planes for the correct perspective.

Figure 5.123. Using the Clone Stamp tool to edit in perspective.

Filter Gallery

Besides being able to retouch just about any image in Photoshop, you can stylize or adjust a photo to give it a certain look. For example, Photoshop can apply a filter to a standard photograph to make it appear as if was painted with watercolor or drawn with chalk and charcoal.

Photoshop's filter menu is filled with a plethora of these types of effects, but unless you know exactly what you're looking for, it can be quite time-consuming having to go through them all and see how your selected image will look with a filter applied. So it's with good reason that Photoshop has a feature called Filter Gallery that enables you to visually apply any of the many artistic and stylistic filtersand even combine themin a single dialog box.

Choose Filter, Filter Gallery, and you're presented with a full-screen dialog box that consists of four sections (see Figure 5.124). The far-left area gives you a preview of your image, and the middle section is where you choose the kind of filter you want to apply. The upper-right section enables you to tweak the individual settings of the filter that's chosen in the center panel, and the lower-right panel allows you to control multiple filters and how they are applied to your image.

Figure 5.124. The Filter Gallery dialog box.

Using Filter Gallery is not only easy and useful, but it's also addictive and fun. The possibilities are endless. Why settle for a standard stock photo for that brochure when you can create an entire stylized look by applying filters?

What makes this feature so powerful is how it enables you to experiment and apply multiple filters to your image. In the lower-right section of the dialog box, use the New Effect Layer button to add another effect (as many as you like), and choose a different filter from the middle panel (see Figure 5.125). Stacking order is important, so you can also drag the filters up and down to see how the appearance changes depending on which filter is applied last. You can also disable an effect by clicking on the eye icon to the immediate left of the effect listing.

Figure 5.125. Applying multiple filters to an image.

Did you Know?

You can also apply filter effects to gradients or patterns that you've created to make interesting and unique backgrounds.

Extract

When we talked about selections way back in the beginning of this chapter, we mentioned that you can use tools such as the Magic Wand and the Magnetic Lasso to help make selections. Many times what you're trying to do is remove the background from a photograph (called silhouetting). Depending on the image, this could be a tedious task, and you might want to try using the Extract filter.

When you choose Filter, Extract, you're presented with another large dialog box, with a large preview of your image in the center (see Figure 5.126). Select the Edge Highlighter tool to trace over the edge of the shape you're trying to silhouette. You can adjust the size of the brush; the goal here is to have the actual edge you're tracing fall into the highlighted area. Make the brush big enough that you can easily trace the edge, but at the same time, don't make it so big that other elements are being highlighted as well (see Figure 5.127).

Figure 5.126. The Extract dialog box.

Figure 5.127. Tracing over the edge of your object with the Edge Highlighter tool.

When you've highlighted the edge, switch to the Fill tool and click on the part of the image you want to keep. The Extract filter removes whatever is not highlighted in your file. Click on the Preview button to see what the results will look like (see Figure 5.128). Click OK when you're done.

Figure 5.128. A preview of the object with the background extracted.

Did you Know?

In my experience, I've found that at times you want to manually silhouette an image (rather than use the Extract filter) because either the actual shape isn't good or you want to enhance it. For example, if a person's hair is blowing in the wind and a few strands are flying in odd directions, you'll want to get rid of those strands, not keep them.

Liquify

Thinking back, one of the highlights of kindergarten for me was finger painting (hey, it wasn't that long ago, was it?). The cool squishy paint, the smell, and, most of all, the ability to mush around and mix the colors to create art worthy of nothing less than my mother's refrigerator door. Although Photoshop can't create bright orange handprints on your classmate's dress, the Liquify feature can come pretty close to adding fun to your day (and Mom will still hang it on the fridge).

Seriously, though, the Liquify filter can be quite useful by enabling you to smudge, pull, and distort your photos. Begin by choosing Filter, Liquify, and once again your entire screen will be filled with a dialog box (see Figure 5.129). Choose any of the Liquify tools along the left of the dialog box, and change the brush size by using the bracket keys on your keyboard. Other options are available in the Tool Options section on the right side of the dialog box, and there's an option to use your pressure-sensitive tablet as well (see Figure 5.130).

Figure 5.129. The Liquify dialog box.

Figure 5.130. Using the Liquify tools to apply distortions to your image.

What's so great about this filter is that you can apply distortions to your file, but you can also reconstruct your image to reverse the effect of your distortions by using the Reconstruct tool. You can also use the Freeze Mask tool to highlight areas that you don't want affected by the distortion tools. If you use the Liquify filter on a low-resolution image, you'll see real-time performance and you'll have a fun time distorting your image. But you won't be having as much fun on high-resolution images because applying distortions to them takes a lot of computing power.

If you've used Illustrator before, you might be familiar with something called mesh. Used for gradients and envelopes, a mesh is a matrix of points used to describe a distortion (in its most basic form). Photoshop incorporated this mesh concept behind the scenes with the Liquify filter; as you use the tools to create your distortions, Photoshop saves all the information as a mesh. At home, you're thinking, "Um, glad to hear thatlet's get on with the lesson already," but this enables you to save your distortion mesh from Photoshop and apply it to other files (see Figure 5.131).

Figure 5.131. The Load and Save Mesh buttons in the Liquify dialog box.

Let's apply the concept to a real-world example. You are working with a low- resolution file in your comps, and then when you get client approval, you'll replace all of your files with high-resolution ones. You can save the mesh from your low-res file and then apply it to your high-res one. To save a mesh, click on the Save Mesh button in the Liquify dialog box, and use the Load Mesh button to load one.

Noise

In physics, the word noise is defined as "a disturbance, especially a random and persistent disturbance, that obscures or reduces the clarity of a signal." But as with most things in life, you can take something that appears to be negative and turn it around, making it into a positivesomething you can use. Sometimes you might have distortion in certain parts of an image, and adding some noise to that area might improve the overall appearance. Here are two examples:

• Most digital cameras save pictures in JPEG format, and the pictures can sometimes contain artifacts (random pixels and anomalies, and so forth). Many times these artifacts appear because of distortion in the Blue channel. Applying some noise to just the Blue channel might result in a smoother and cleaner image overall.

• Gradients that span large areas (entire pages, spreads, or large documents, such as movie posters) can print with bandingvisible shifts or "steps" of color. This is especially evident with light colors, such as yellow. Adding a bit of noise can visually break up these steps and produce a smoother-looking gradient (although more grainy in appearance).

Did you Know?

Adding noise is also a great way to create background textures and special effects.

To add noise to a selection (or, if nothing is selected, an entire image), choose Filter, Noise, Add Noise. Use the Amount slider to control how much noise is added, and choose Uniform or Gaussian distribution (see Figure 5.132). I find that when you're adding smaller doses of noise, Gaussian looks best, but Uniform gives a better appearance when you're adding large amounts of noise. The Monochromatic option adds only black noise (very useful for mezzotintlike effects).

Figure 5.132. Applying noise to a selection.

Of course, sometimes you'll want to remove noise from an image. Digital images or scans can have artifacts that take away from the overall look of the image. Choose Filter, Noise, Reduce Noise to make this adjustment (see Figure 5.133).

Figure 5.133. Reducing the noise in an image.