Understanding Adobe Photoshop CS4- P2 pot

18 Chapter 2 Photoshop’s Interface Adjustments One of the most common tasks in Photoshop is making adjust- ments to images to fi x tone and color. Photoshop CS4 adds a new Adjustments panel to provide easy access to the most common commands. The adjustments are grouped into three categories: • Tonal controls. Use these controls to adjust Brightness/Con- trast, Levels, Curves, and Exposure in a nondestructive fashion. • Color controls. Use these controls to adjust Hue/Saturation, Color Balance, Black & White conversion, Photo Filter, and Channel Mixer properties. • Creative/Advanced controls. These controls are special purpose adjustments and include Invert, Posterize, Threshold, Gradient Map, and Selective Color. You’ll also fi nd a useful list of presets for quick access to common adjustments as well as custom settings you create. You’ll explore these adjustments more in later chapters. Masks Photoshop uses masks to obscure parts of an associated item. In fact, you can apply a mask to a layer, a vector, or a fi lter. Photoshop CS4 offers precise control over masks including the ability to adjust their density and edges. Masks are a useful way to erase parts of a layer non- destructively, which allows for future changes. They can also be used to isolate an adjustment to only parts of an image. You’ll see multiple masks in use in the sample document to isolate the effects of color correction. You’ll explore masks in depth in Chapter 7, “Layer Masking.” Color Don’t confuse the Color panel with the color mode of the document. The Color panel allows you to modify and select colors using six different color models. You can choose colors using RGB sliders or the more intuitive Hue Saturation and Brightness (HSB) model. To adjust color, move Understanding the Interface 19 the sliders for the corresponding value. Sliding the Red slider to the right increases the amount of red in the new color. Choosing colors is independent of image mode in that you can use a CMYK model for an RGB image. However, picking a color to use in a grayscale document will not introduce color into that image. Spend some time exploring the Color panel and fi nd a method that works best for you. Clicking on a color swatch opens the powerful Color Picker, which unlocks a larger visual interface for exploring color and enhances the use of the Eyedropper tool to sample color from a source image. You’ll use color in several of the chapters in this book, and the Color panel and Color Picker are fairly easy to understand. Swatches The Swatches panel is like a painter’s palette in that it holds several colors ready to use. Several colors are loaded by default, which are useful when painting or using fi lters that utilize those colors. If you click the panel’s submenu, you’ll discover many more swatch books to load for specialty purposes like Web browser colors, spot color printing, or thematic color swatches (such as a blue saturated range). TEMPORARY BANISHMENT OF PANELS If you want to hide your panels, you can quickly toggle them off and on: • Press the Tab key to hide all the panels. • Press the Tab key again and they return. • Press Shift+Tab to hide everything except the Options bar and toolbox. • To focus on only on your image, press the F key once to go to Full Screen Mode With Menu Bar mode. Press the F key again to go to Full Screen and hide all the user interface elements. Press the F key once more to cycle to Standard Screen Mode. 20 Chapter 2 Photoshop’s Interface Styles The Styles panel is where you can visually access Layer Styles. These are the combination of layer effects (which can be ap- plied singularly to create effects such as beveled edges, drop shadows, or glows). Effects are most useful in combination, and advanced photorealistic effects can be achieved. Photoshop ships with several built-in styles, and many more are available for download from Adobe’s Web site (www.adobe.com/exchange) as well as many other Photoshop sites. Layer Styles are frequently used for text and image effects but can also be harnessed for Web rollover effects for buttons. For more on Layer Styles, be sure to read Chapter 13, “Layer Styles.” Navigator While working with photos, you’ll often need to zoom in to touch up an image. It may sound cliché, but it’s easy to lose your per- spective when working in Photoshop. When you zoom in to a pixel level for image touchup, you often won’t be able to see the entire image onscreen. This is where the Navigator comes in handy: 1. Open the photo Ch02_Butterfl y.jpg from the Chapter 2 folder on the CD. 2. Select the Zoom tool from the toolbox or press Z (the tool looks like a magnifying glass). Click multiple times near the butter- fl y’s head to zoom in. 3. Call up the Navigator panel by choosing Window > Navigator. 4. You can now navigate within your photo: • Drag the red view box around the thumbnail to pan within the image. • Resize the Navigator panel for a larger image preview. • Move the Zoom slider to zoom in or out on the image. • Click the Zoom Out or Zoom In buttons to jump a uniform magnifi cation. VIDEO TRAINING Using the Navigator 6 Understanding the Interface 21 Histogram While color correcting or adjusting exposure, the histogram can be a great help. This graph illustrates how the pixels in the image are distributed across brightness levels. To read a histogram, start at the left edge, which shows the shadow regions. The middle shows the midtones (where most adjustments to an image are made), and to the right are the highlights. Image touchup and enhancement are covered in Chapter 10. You may want to leave the Histogram panel open as you work, because it is an easy way to learn to read the graphical details of a digital image. Info The Info panel is a useful place to fi nd a plethora of image information, even when using the default options. You can get information about color values as well as precise details about the active tool. However, by customizing the panel you can make it truly useful: 1. Select the Info panel by choosing Window > Info or by pressing F8. 2. From the Info panel submenu (the triangle in the upper-right corner) choose Panel Options. The Histogram panel has been set to Show All Channels view. You can choose this interface by clicking the triangle in the upper-right corner and choosing All Channels view. The top histogram is a composite histogram for the red, green, and blue channels combined; the next three show them individually. 22 Chapter 2 Photoshop’s Interface 3. The resulting dialog box has several options; I recommend the following choices for a new user: • Leave Mode set to Actual Color. • Set Second Color Readout to CMYK if you’re doing print work, or set it to RGB color if you are preparing images to use on the Internet or in video exclusively. • Set Mouse Coordinates to Pixels. • Enable the following choices under Status Information: Docu- ment Sizes, Document Profi le, and Document Dimensions. • The last option, Show Tool Hints, provides a detailed ex- planation for each tool you select from the toolbox. 4. Click OK. History The History panel will quickly become your best friend. It’s here that Photoshop keeps a list of what you have done to the image since you opened it. By default Photoshop keeps track of the last 20 steps performed on an image, but you can modify this number. A higher number means more levels to undo. 1. Press Command/Ctrl+K to call up the Photoshop Preferences dialog box. 2. In the Performance section, change History States to a higher number, such as 100. Note that more levels of undo requires more RAM, so you may need to balance this number if your system is under-equipped. 3. Click OK. Actions Actions are among the least-used features of Photoshop but are the most powerful. Actions allow for visual scripting, which means you can record commands or adjustments that you need on one image and play them back on other images. For example, you could record an action that adjusts the size of an image, runs an adjustment to lighten the image, and then converts it to a TIFF fi le for commercial printing. You could then play that series of commands back on another image or even batch process an entire Understanding the Interface 23 folder of images (which can eliminate boring, repetitive work). Actions can be very useful for both design and production tasks. You’ll explore Actions fully in Chapter 15, “Actions and Automation.” A CUSTOM WORKSPACE You’ll fi nd that the more you work with Photoshop the more you’ll want to use different tools for different situations. For example, you’ll want Layer Styles and the Color Picker handy for text work, but you’ll turn toward the Histogram and Adjustment panels when doing image restoration. You can save any combination and arrangement of panels that you want to reuse. Then you can access it in one click with Workspaces. Effectively, using Workspaces enables you to switch between different production tasks (such as image touchup and type work) with ease. Plus, it is a way to customize the application and make it feel more welcoming to your way of working. Try it out. 1. Open the windows you need and arrange them into the desired positions. 2. To save the current workspace layout, click the Workspace switcher and choose Save Workspace. 3. Enter a unique name for the workspace and click OK. To activate a workspace, choose it from the Workspace switcher in the Application bar. To update a workspace, resave it with the same name. To delete a workspace, click the Workspace switcher and choose Delete Workspace. Character While Photoshop began its life as an image editor (essentially a digital darkroom), it has greatly evolved over the years to also include a powerful text tool. Many people start and fi nish their entire designs inside Pho- toshop. These designs include advertisements, posters, pack- aging, and DVD menus. 24 Chapter 2 Photoshop’s Interface A close look at the Character panel reveals complex control over the size, style, and positioning of individual characters within a word. The Type tool is explained in signifi cant depth in Chapter 12, “Using the Type Tool.” Paragraph The Paragraph panel contains controls that impact paragraph text. When using the Type tool, you can click and type, which creates point type. Or, for more control, you can click and drag to create a text block and then access paragraph type. This causes the text to have boundaries and wrap when it hits a margin. Within a text block, you have a signifi cant level of control on how your type is aligned and justifi ed. For much more on text, see Chapter 12. TIP Docking Panels To save space, any fl oating panel can be collapsed to an icon. Simply drag a panel to any edge and a blue line will appear (which indicates where the panel will dock). The most common place to dock panels is on the right edge of the screen, but they can be docked on the left or bottom edges as well. Acquiring Digital Images 3 While Photoshop is a great tool for many tasks, most of them center on the sizing, manipulation, and processing of digital images. Even though their contents may vary, all digital images are es- sentially the same: They are composed of pixels that contain color and luminance information. Photoshop’s powerful features allow you to adjust those pixels to better match your needs. And while the destination may be the same, the path your digital images take to get inside Photoshop will vary. Some may start out as digi- tal images acquired with a still camera, whereas others may be loaded via a scanner. You might also search online resources to fi nd specialized images. Let’s take a look at the many ways to acquire your digital images. Digital Cameras This book will not teach you how to use your digi- tal camera. Many excellent books on that subject as well as classes are offered. What this book will address is how the pixels are converted, what fi le format you should choose to shoot your images, and how to transfer them to your computer. Digital Camera Technology Shooting a photo digitally produces a less ac- curate image than scanning a photo shot on fi lm and scanned with a fl atbed scanner using a Pixels in detail: When you zoom into an image at 1600% magnifi cation, the pixels are very easy to see. You can open the photo Ch03_Car_in_Mirror.tif from the Chapter 3 folder and use the Zoom tool (Z) to magnify the image. In fact, you can zoom up to 3200%, which makes pixel viewing quite easy. PHOTO BY JIM BALL Sensors in a digital camera acquire an image by converting light into pixel data. 26 Chapter 3 Acquiring Digital Images high spi setting. This is because digital cameras capture data using photosensitive electronic sen- sors. These sensors record brightness levels on a per-pixel basis. However, the sensors are usually covered with a patterned color fi lter that has red, green, and blue areas. While the fi lter attempts to capture all detail that the lens sees, it is unable to due to its design. The fi lter used is typically the Bayer fi lter ar- rangement, which contains two green pixels, one red pixel, and one blue pixel. The Bayer fi lter uses more green because the human eye has an increased sensitivity to green. This fi lter allows the image to record the brightness of a single pri- mary color (red, green, or blue) because digital cameras work in the RGB color space. The RGB values combine using the additive color theory (which was briefl y discussed in Chapter 1, “Digital Imaging Fundamentals”) and form an image when viewed from a suitable distance. Not all the properties of fi lm can be fully imitated by the computer sensors in a digital camera, so the camera must interpolate the color information of neighboring pixels. This averaging produces an anti-aliased image, which can show visible softening. When anti-aliasing is present, hard edges are blended into one another. Sometimes this can be desirable (with low-resolution Internet graphics where you reduce fi le size by limiting color). Other times, anti-aliasing can produce an undesirable softness when you print an image. Depending on the colors in the original image, a digital camera might only capture as little as one-fourth of the color detail. For example, if you had a desert scene with lots of red detail and little green or blue, the sensor would rely on the red areas of the fi lter (which only cover a fourth of the sensor face). Does this mean you should shoot fi lm only? Of course not; I shoot both. But it’s important to shoot for what you need. There are strengths and weakness of both fi lm and digital capture (as well as several stylistic decisions). Ultimately, fi lm captures a high-quality image that can be optically enlarged using the negative. However, digital capture can be more convenient and affordable because you get instant feedback on the images you have just taken, and you eliminate the time-consuming process and costs associated with developing the fi lm. The Bayer fi lter arrangement uses an arrangement of red, green, and blue pixels and is very common in digital cameras. There are more green pixels because the human eye is more sensi- tive to green information. Digital Cameras 27 It is important to shoot at a high pixel count (which can be accom- plished by setting the camera to shoot in a high- or best-quality mode). You can always crop or shrink the image for output or display, but you should do your best to avoid enlarging the image. When a digital image is enlarged, it can create unwanted image softness or pixelization (a visible blockiness). Capture as much pixel data as possible to minimize digital upsampling (increasing the resolution of the image). Shooting JPEG vs. RAW When digital cameras became commercially available, the memory cards used to store pictures were very expensive. Many photographers could not afford multiple or high-capacity cards, so they wanted more images to fi t on a single, smaller card. Many users also emailed their pictures to friends and family. Small fi le sizes enabled consumers who lacked an understanding of digital imaging to attach photos to emails with minimum technical head- aches. With these two scenarios in mind, manufacturers turned to an Internet-friendly format, JPEG (Joint Photographic Experts Group). It was a proven technology and one that was familiar to many users. The JPEG format is extremely common because most hardware and software manufacturers have built support for it into their products. The JPEG format is also extremely effi cient at compressing images, and it is a good format for continuous tone images, such as photos. A JPEG fi le looks for areas where pixel detail is repeated, such as the color white on every key of your computer keyboard. The fi le then discards repeated infor- mation and tells the computer to repeat certain color values or data to re-create the image. While JPEG is a good format for distributing images (due to their compatibility and small fi le size), it is not great for image acquisition or pro- duction. A JPEG fi le is lossy, meaning that every time you modify it in Photoshop and resave, ad- ditional compression is applied to the image. Over subsequent compressions, the image quality can noticeably deteriorate. This is similar to the act of The JPEG Options box is available when you modify a JPEG fi le with Photoshop. When saving, you can adjust the Qual- ity slider to reduce fi le size. It is best to leave Quality set to maximum if you will be making future edits to the image: This applies the least compression that could damage the image’s appearance. VIDEO TRAINING Importing Images with Adobe Bridge 7 [...]... lets you easily adjust white balance within Photoshop Each manufacturer treats the format differently, using a proprietary format Fortunately, Photoshop frequently updates its raw technology to support the newest cameras on the market To fi nd out if you can access a particular camera format from within Photoshop, visit Adobe s Web site at www .adobe. com/products/ photoshop/ cameraraw.html Because the raw... entries in the manufacturers have been slow to adopt it (some even refusing) At this Adobe Help Center Fortupoint, DNG files are a useful way to archive raw files and attach addinately, the Camera Raw dialog tional metadata You can find out more about DNG by visiting Adobe s box is fairly intuitive, especially Web site at www .adobe. com/products/dng/main.html once you understand the concepts of adjusting images... something that most people are short of these days TIP Workaround for Unsupported Cameras If Photoshop does not support a particular raw format used by your camera, use the software that shipped with the camera The image can be converted into a 16 bit TIFF image (a high-quality file with no compression), which Photoshop can open Newer digital cameras, generally the pro models, offer newer formats, typically... benefits and should be fully explored by reading the documentation that accompanies your camera 8 The Adobe Camera Raw dialog box is a versatile environment for “developing” your pictures The image Ch03_Peppers.NEF is included on the CD Choose File > Open and navigate to the file in the Chapter 3 folder In Photoshop CS4, you can even make localized adjustments by painting an area and then using sliders... 29 VIDEO TRAINING Camera Raw Interface 30 Chapter 3 Acquiring Digital Images The Camera Raw dialog box has continued to evolve since it was fi rst introduced as a purIn 2004 Adobe released the Digital Negative Specifichased add-on to Photoshop 7 cation (DNG) file format The code and specifications Subsequent versions of Photowere made publicly available so manufacturers could shop have updated the user inbuild... has a greater tonal range; hence, there is a better exposure for shadows and highlights This extra information makes your work in Photoshop easier because it adds greater flexibility and control in image adjustments and color correction You should have less work to do in Photoshop as well, since the image captured has more color information than a JPEG would have Raw fi les can be two to six times larger... don’t work as well as a dedicated specialized fi lm scanner These options often just add to the cost of the scanner 31 NOTE Transferring Files The actual transfer of photos is not handled by Photoshop Rather, you can use Adobe Bridge CS4, which includes a Photo Downloader (File > Get Photos from Camera) If you are not using Bridge, the files are handled natively by your computer’s operating system Just manually... allows you to make decisions about cropping and reformatting 34 Chapter 3 Acquiring Digital Images 3 Place your photos on the scanner and make NOTE Crooked Scan? Fix It Later with Photoshop If you get crooked photos, you can use a Photoshop automation command to automatically crop and straighten your images Simply open the file, and then select File > Automate > Crop and Straighten Photos You’ll find two... skipped ahead or just skimmed that chapter, go back—a solid understanding of those concepts is required Quite simply, you must know the capabilities of your scanner or digital camera to process information Previous chapters also briefly discussed output requirements for different formats The second part of the image-sizing puzzle is a clear understanding of these output requirements What resolution does... image that is not any sharper than the original Choose an Interpolation Method When you resample an image, Photoshop creates new pixels Those new pixels are created based on the neighboring pixels How those new pixels are formed is determined by the interpola- Resampling tion method you specify Photoshop offers up to five methods to resample your image Choose one of the following methods: • Nearest Neighbor: . within Photoshop, visit Adobe s Web site at www .adobe. com/products/ photoshop/ cameraraw.html. Because the raw data is unprocessed, you must essentially “de- velop” the image data inside Photoshop. . can be achieved. Photoshop ships with several built-in styles, and many more are available for download from Adobe s Web site (www .adobe. com/exchange) as well as many other Photoshop sites 18 Chapter 2 Photoshop s Interface Adjustments One of the most common tasks in Photoshop is making adjust- ments to images to fi x tone and color. Photoshop CS4 adds a new Adjustments