David D. Busch - Digital Retouching and Compositing: Photographers Guide

One of the most important and often overlooked developments of the computer age is the ability of Photoshop, and image editing tools like it, to subtly (or dramatically) alter the appearance of images we view. Today, we're so accustomed to assuming that a startling image may have been "photoshopped" that we sometimes forget that sayings like "Seeing is believing!" once held a solid grain of truth. Photographs in supermarket tabloids of farmers wrestling with pig-sized grasshoppers and images of the Great Pyramid of Giza relocated slightly to create a better composition on the cover of National Geographic remind us that our eyes and brains are easily tricked.

Until recently, realistic image fakery required either a great deal of planning or monstrous expense. National Geographic, for example, employed a gazillion-dollar Scitex laser scanner to nudge two pyramids closer together into a vertical composition for its controversial February 1982 cover. Today, anyone with a $50 scanner and a copy of Photoshop can do the same thing, and probably do a better job of itif they've read this book!

In general, these newfound capabilities are good things. Most of us aren't interested in assembling a photograph that shows George Bush having a conference with Mohandas Gandhi, for nefarious purposes or otherwise. We're more interested in removing bags under the eyes in a portrait of a loved one, or banishing an ex-brother-in-law from a family portrait. We'd like to disguise dust spots, bring back vibrant color to a faded 50's-era snapshot, or remove a telephone pole that seems to be growing out of someone's head.

These are all things you can easily accomplish with Photoshop, if you know how. This book shows you the secrets of retouching images and how to create new ones through seamless compositing techniques. This chapter provides a little background on both, and lists the skills you'll need to master to become a proficient image manipulator.

Photography has always been part craft, part science, and part fine art, with a little alchemy and magic mixed in. Early photographers were often skilled artisans who built their own cameras, amateur chemists who sensitized photographic plates, as well as artists. Digital imaging cranks up the science component several notches, giving the artist in all of us more powerful brushes and an infinite palette of colors, tools, and effects.

Photoshop offers a bulging toolbox of implements that can handle every imaginable retouching and compositing chore. In the non-digital world, such a toolbox would contain brushes, etching knives, dyes, pigments, a set of the venerable Marshall's Photo Oils, and maybe an airbrush. Photoshop contains the equivalent of all these tools, plus many more. This section is an overview of the most important capabilities of Photoshop for making the kinds of modifications we explore in this book. All of them are covered in more detail in later chapters.

The selection tools are probably the single most important set of Photoshop features you need to master. Only by selecting exactly the right area of an image can you apply changes only to the portion that will benefit from the modification. For example, you may want the main subject of a photograph to stand out a little more dramatically. Sharpening the subject and/or blurring the background a little can produce the effect you're looking for. However, to apply Photoshop's sharpening or blurring effects, you must first select the area to which the effects will be applied. That may be simple (if, for example, the portion of the image is rectangular or circular and can be easily selected using the Rectangular or Elliptical Marquee tools) or more difficult (if the image area has fuzzy, furry, or irregular edges).

Photoshop includes tools that make selecting much simpler, including a Magnetic Lasso that "sticks" to the edges of objects, a Color Range command that grabs only pixels of a certain range of hues, and the invaluable Extract feature, shown in ."

Photoshop's layers capabilities are arguably the second most important tool in your arsenal. Layers allow you to separate portions of an image into individual overlay-like stacks that you can manipulate individually and then combine in a variety of ways. If you're working on a shot of a soccer game, for example, you can extract the soccer ball, put it into its own layer, then move it anywhere on the field. Blur the ball to simulate motion, make it semitransparent as if it were beaming up to a starship, or change its colors in dramatic ways.

Layers are indispensable when you're compositing multiple images, but they can also help when retouching a photo. You can, for instance, paint various hues on separate layers to convert a black-and-white image to full color, or create a layer of texture that masks defects in an image. Master Photoshop's layer tools and you'll find a vast new array of capabilities at your fingertips.

Using layers effectively involves working in tandem with other tools, so there is no separate chapter on layers in this first section of the book. Although learning selection tools is something you can do independently, the use of layers changes, depending on the task at hand. You'll find lots of tips for working with layers in Parts of this book.

These tools help you adjust the size of an image or selection, modify the area contained within the image's borders, and rotate or flip it to create a new perspective.

Photoshop includes several tools that let you resize an entire digital image, or rescale portions of the image while leaving the rest of the picture untouched. Go ahead, make that soccer ball huge. Enlarge that tree in your front yard to see what it will look like in 15 years. Make your company's products larger in comparison to your competitors'. Image scaling tools can be used to resize a picture or object proportionately (that is, the same amount in all directions) or in only one direction. I've used sizing to make myself look taller and thinner, to stretch out a wall, or make a patch of sky I was pasting into an image wider to fill a larger area.

Cropping tools let you trim excess image area from your photos, providing a better composed image or one that better fits the "hole" you have for it in a desktop publication, picture frame, or a collage that you're compositing together.

Use orientation tools to flip an image left to right or vertically, to suit a composition, or just to provide a new view. Photoshop also allows you to rotate images around an axis of your choice so you can, for example, appear to be climbing a steep slope when, in the original picture, you were walking on flat ground and merely leaning forward.

You needn't be an artist to use Photoshop's broad array of painting tools. You may need to convert a fairly dark background to an inky black one, and find that a fuzzy brush used with a black tone is your best friend. Or, you might need to copy some background texture over a portion of an image to hide, for instance, an unfortunately located fire hydrant. Photoshop boasts a variety of brush tips and shapes and many different tools that use those brushes in different ways.

The Clone Stamp tool, represented by a rubber stamp icon, is one of them. It duplicates part of an image, pixel by pixel, in a location of your choice. The stamp analogy isn't perfect, however, because you're actually drawing with a brush that you can size and control in other ways allowed by Photoshop, such as transparency of the image laid down.