14. Manipulating Images with Filters

Introduction

Adobe Photoshop filters are a designer’s dream come true. With filters you can turn a photograph into an oil painting or a watercolor; you can even change night into day. Photoshop’s Filter menu includes no less than 105 highly creative filters, which can be applied once, reapplied, or combined with other filters to create any effect your imagination can dream up.

The potential combination of filters and images literally runs into the millions. This means that Photoshop filters are truly an undiscovered territory. As a matter of fact, the Filter Gallery lets you view the effects of one or more filters on the active document. This level of power gives you unbelievable creative control over your images.

Other commands, such as the Fade command, let you reduce the effect of the applied filter. You can even apply a blending mode to the final image. In addition, you can utilize a channel mask to control how the filter is applied to the image. You could also use a black to white gradient channel mask to slowly fade the effects of the filter from left to right.

Photoshop even lets you protect your intellectual property by embedding a customizable watermark into the image that is almost invisible to see, and virtually impossible to remove. In fact, you can print an image that contains a watermark, run it off on a copy machine and rescan it, and the watermark is still there. Now that’s protection.

Take a moment to view some of the various filter effects that Photoshop offers. Because there are 105 filters available, we can’t show you all of them, but we think you’ll enjoy viewing the selection at the end of the chapter.

Working with the Filter Gallery

The Filter Gallery enables you to maintain complete and total control over Photoshop’s filters. In essence, the Filter Gallery gives you access to all of Photoshop’s filters and lets you apply the filters to any raster image, while viewing a large preview of the results. The Filter Gallery dialog box is composed of three sections—Image Preview, Filter Selection, and Filter Controls. When you use the Filter Gallery to modify the image, you see exactly how the image will look; there is no guesswork involved. When you apply a filter to an image, you are physically remapping the pixel information within the image. Photoshop contains 105 filters and the combinations of those filters are astronomical. If you are a math wizard, you know there are over 100 million combinations available, and that means no one has yet discovered all the ways you can manipulate an image in Photoshop...have fun trying.

Work with the Filter Gallery

Click a filter from the expanded list to view its default effects on the image.

Modify the effects of the filter using the filter controls.

To temporarily hide the Filter Selections, click the Show/Hide Filter Thumbnails button, located to the left of the OK button.

Click OK.

Creating and Working with Smart Filters

When you apply a filter to a Smart Object, the filter becomes a nondestructive Smart Filter. If you don’t have a Smart Object, you can convert a normal layer for Smart Filters. Smart Filters appear in the Layers panel below the Smart Object layer, where you can show or hide them independently. You can apply any filter to a Smart Object except Liquify and Vanishing Point.

Create and Work with Smart Filters

Applying Multiple Filters to an Image

Not only does Photoshop’s Filter Gallery let you apply and view a filter effect, it lets you view the multiple effects of two or more filters. The Filter Gallery has its own Layers panel, and you can have multiple filter layers. The order of the filters influences their impact on the image, so when you use more than one filter, try dragging the filter layer up or down in the stack to see the different possibilities. Experiment with different stacking orders to create unique, eye-popping special effects.

Apply Multiple Filters to an Image

Modifying Images with Liquify

The Liquify filter gives you amazing control over an image. For example, you can distort the image pixels almost as if the image were an oil painting that had yet to dry. In addition, you can magnify specific areas of an image or reduce them in size. The Liquify filter lets you push, pull, rotate, reflect, pucker, and bloat any area of an image. The distortions you create can be subtle or drastic, which makes the Liquify command a powerful tool for retouching images as well as for creating artistic effects.

Modify Images with Liquify

Working with Liquify Tool Options

The Liquify Tool options control the brush tip. Since all the Liquify commands are executed with a brush, it’s important to understand how you control the brush tip. When you apply the brush stroke, the faster you drag the mouse, the less effect is applied to the image; if you drag slowly, you gain more control and the effect is more intense. Practice dragging the cursor over the image to produce different effects, and if you make a mistake, don’t forget the undo key—Ctrl+Z (Win), (Mac).

Work with Liquify Tool Options

Working with Liquify Mask Options

When you work with an image that contains a selection or mask, you can use that information to control how the Liquify command adjusts the image. Think of the mask as a visual representation of the work areas of the image. Creating a mask gives you precise control over what portions of the image are modified.

Work with Liquify Mask Options

Working with Liquify View Options

The Liquify View Options control what you see in the preview window. For example, you can choose to view or hide a mask, or even change its color. If the image you’re working on is in a transparent layer you can even choose to view the image with or without the other image layers. How you view the image is up to you; however, having choices gives you greater control over the final results.

Work with Liquify View Options

Creating a Liquify Mesh

You may have noticed the Load Mesh and Save Mesh buttons, located at the top of the Liquify dialog box. A mesh is a predefined Liquify operation. When you activate the mesh option, a mesh or grid is placed over the image, and then as you use the Liquify tools, the mesh distorts and bends. After applying a lot of work to a particular image, it’s quite possible you might want to use that exact mesh on another image. That’s where the Load Mesh and Save Mesh options come into play. With the click of a button you can create a mesh and use it over and over again.

Create a Liquify Mesh

Applying a Liquify Mesh

Applying a mesh to an image is a lot easier than redoing a particular Liquify operation and to be honest, it would be virtually impossible to reproduce a Liquify adjustment from scratch. That’s why Adobe gives you the option of creating, saving, and loading your very own personalized meshes.

Apply a Liquify Mesh

Using the Lens Blur Filter

The Lens Blur filter creates a varying depth of field so that certain objects stay in focus and other areas become blurred. What stays in focus and what is blurred is determined by a user-defined selection or alpha channel. When the filter is activated, a depth map is created to determine the three-dimensional position of the pixels in an image. If you use an alpha channel, the black areas in the alpha channel are at the front of the photo, and the white areas are in the distance. Experiment with selections and alpha channel masks to see how precisely you can control the visual effect of blurring in an image.

Use the Lens Blur Filter

Working with Photo Filters

The Photo Filter command reproduces the same effect of placing a colored filter in front of the camera lens when you take a picture. Photographers place colored filters in front of a camera lens to adjust the color balance of the image and control the color temperature of the light transmitted through the lens. In addition to simulating a color filter, the Photo Filter command also lets you select a color preset and apply a specific hue adjustment to an image. If you want to apply a custom color adjustment, the Photo Filter command lets you specify a user-defined color using the Adobe Color Picker.

Work with Photo Filters

Click OK.

Blending Modes and Filter Effects

When Adobe introduced the Filter Gallery in Photoshop CS, it finally gave designers the ability to view the effects of multiple filters applied to a single image. While this changed forever how we apply filters to an image, there is one more creative way to work—Blending Modes. For example, you can make a copy of an image, apply a separate filter effect to each layer, and then use the Blending Modes option to create a totally different image. While this is not a new technique, the results of combining two or more layers together, each with a different filter effect, can produce quite stunning results.

Work with Blending Modes and Filter Effects

Building Custom Patterns

The Pattern Maker filter lets you create your own distinctive patterns, based on image information in the active document, or clipboard memory. Since the pattern is based on sample data, it shares the visual characteristics of the sample. For example, if you sample an image of a cloudy sky, the Pattern Maker generates a tile-like pattern that is different from the sample but still retains the elements of a cloudy sky. You can even generate multiple patterns from the same sample.

Build Custom Patterns

Select from the available Tile Generation options:

  Use Clipboard As Sample.Uses the pixel information contained in the Clipboard as the tile-generating pattern.

  Use Image Size.Creates a tile pattern the size of the original image.

  Width.Enter a value (1 to 800), or click the black triangle and drag the slider left or right to define a width.

  Height.Enter a value (1 to 800), or click the black triangle and drag the slider left or right to define a height.

  Offset.Click the list arrow, and then click None, Horizontal, or Vertical.

  Amount.Enter a percentage value (1% to 100%), or click the black triangle and drag the slider left or right.

  Smoothness.Click the list arrow, and then select a value of 1, 2, or 3.

  Sample Detail.Enter a value from 3 to 21, or click the black triangle and drag the slider left or right.

  Show.Click the list arrow, and then select between the generated sample and the original image.

  Tile Boundaries.Select the check box to view the tile edges in the preview window. Click on the color box, and then select an alternate color.

Scroll through your tile patterns using the left/right arrow keys underneath the Tile History preview. Stop when you see the pattern you want.

Click OK.

Using the Fade Command

Photoshop’s Fade command is a one-shot chance to change your mind. For example, you’ve just applied the Find Edges filter to an image. You like the look but the effect is too dramatic. What you really want to do is tone down the effect. Unfortunately, filter effects don’t fade like a gradient; they are simply applied, all or nothing, to the image. You could create a copy of the original layer, apply the effect to the copy, and then use Layer transparency and blending mode options to merge the effect with the image, but there’s an easier way. Just use the Fade command.

Use the Fade Command

Controlling Filters Using Selections

When you apply a filter to an image, Photoshop applies the filter equally to the entire image. Unfortunately, that might not be what you had in mind. For example, you might want to apply the Gaussian Blur filter to a portion of the image. In that case, Photoshop’s selection tools come to the rescue. The primary purpose of making a selection is to define a work area, and when you select an area before applying a filter, the only area impacted by the filter will be the selected area.

Control Filters Using Selections

Using a Channel Mask to Control Filter Effects

Photoshop’s filters can be applied to any raster image. In addition, filters can be controlled with the use of selections. You can use any of Photoshop’s selection tools to define a working area. However, simple selections are limited in what they can do. Although the edge of selections can be modified by feathering, the inside area of the selection is completely selected. What if you want to apply a filter in a completely different way? For example, what if you want to apply a filter that is stronger on the right side of the image, and slowly tapers off from left to right? In that case a simple selection won’t help, but a Channel mask will do exactly what you need.

Use a Channel Mask to Control Filter Effects

Protecting Images with Watermarks

Digital watermarks are designed to protect your intellectual property. When you embed a digital watermark, it actually inserts the watermark information as visible noise into the image. This means that someone can copy your image, scan it, and the watermark is still part of the image. To embed a digital watermark, you must first register with Digimarc Corporation, which maintains a database of artists, designers, and photographers along with their contact information. You can then embed the Digimarc ID in your images, along with information such as the copyright year or a restricted-use identifier.

Protect Images with Watermarks

Viewing Various Filter Effects

Photoshop provides a bountiful selection of filters, 105 to be exact. Take a moment to view some of the various filter effects that Photoshop offers. The original image is shown to the right, and we’ve displayed some common filters on the following pages. A good thing to think about when using filters is your original image. Look at the background colors, and see if they will look good with some of the filters. The best thing to do is open an image that has a lot of varied details, and then apply some filters to see what looks good to you.

Various Filter Effects