Photoshop cs5 cho nhiếp ảnh gia part 32 pdf

193 ■ WORKFLOWS AND FIRST STEPS 5 Ph oto by EllEn An on Workflows and First Steps Once you have Photoshop or Elements set up the way you want it and you’ve used Adobe Camera Raw (ACR) to make most of your tonal and color changes, you may still have a little more work to do. If you get in the habit of following a routine approach when optimizing your images, you’ll find that you work more efficiently. We’ll suggest two versions of an overall workflow that you can modify to suit your particular needs. One version is more flexible and takes advantage of Smart Objects and Smart Filters, while the other is more traditional. Chapter Contents Understanding Layers Flexible and Traditional Workflows Cropping and Straightening in Photoshop Doing Cleanup in Photoshop 607343c05.indd 193 4/13/10 2:44:05 PM 194 c h a p t e r 5: WORKFLOWS AND FIRST STEPS ■ Understanding Layers Before proceeding further with the workflow, you need to understand layers—what they are, why they’re so important, and how to make them. Most Photoshop novices are initially intimidated by the concept of layers. But in reality, they’re quite simple to understand. Let’s begin by thinking of a couple of prints that are the same size. If you took one print and placed it on top of the other print, you would no longer be able to see the print that’s on the bottom. You know it’s there, and you know if you remove the top print or make a hole in the top print that you would see the print that’s under- neath. But when one print is simply on top of the other, you see only the top print. Those prints are actually two layers. Agreed? In Photoshop each of these prints is called a pixel layer. Pixel layers contain pixels, which are the building blocks of your image. Pixel layers work much the same way as stacking prints on top of one another. Whatever pixel layer is on top is what you see. Note: Right now we are discussing how pixel layers behave in the Normal blending mode. Later in this book we’ll discuss some more advanced behaviors of layers using different blending modes. For now, we’ll keep it simple. But wait—there are actually two types of layers of concern to photographers: layers that have pixels, and adjustment layers, which don’t have any pixels at all! Adjust- ment layers are simply instructions for changing the appearance of the pixel layers. For example, they may contain instructions to make the pixels lighter or darker; more or less contrasty; more or less saturated; or bluer, redder, and so on. In other words, adjust- ment layers modify the appearance of your image but not the content. It would be simi- lar to putting a filter over your top print in our analogy and viewing the print through the filter. Your print would look warmer if it were a slightly yellow filter, bluer if it were a blue filter, and so on. The filter would change the appearance of your print but not the content. Note: Adjustment layers modify the appearance of every pixel layer below them. You could perform all the modifications you make in adjustment layers directly on your pixels by choosing Image > Adjustments and selecting the type of adjustment you want to make. But that’s exactly what we want you to avoid doing! Every time you work directly on a pixel, you damage it and you risk losing some quality in your final output. By using adjustment layers, you can see the changes you have made, but they are not applied to the pixels until you either print the file or flatten it. This way, you can make multiple changes and affect the pixels only once. 607343c05.indd 194 4/13/10 2:44:05 PM 195 ■ U NDE RSTA NDI NG L AY ERS Even better is the flexibility that working in layers gives you. You can return to your image at any time in the future, even after closing it, as long as you have saved the image file with the layers intact, and you’ll be able to modify the adjustments you made. You can increase them, decrease them, eliminate them, and so on—all without damaging your pixels. If the Adjustments panel (shown in Figure 5.1) is not already visible, click the Adjustment panel icon or go to Window > Adjustments and toggle it on. Choosing any of the specific adjustments automatically opens the specific Adjustments dia log and also creates a new layer in the Layers panel. Icons are shown for each of the adjustments, but when you hover your cursor over any of the icons, the name of the adjustment appears in the upper left of the dialog. Almost all the adjustments that are available from Images > Adjustments in the menu bar are available from this list. In addition, if you click the disclosure icon at the top right of the dialog, a text list of all the adjust- ments will appear. Alternatively, you can still click the Create New Adjustment Layer icon at the bottom of the Layers panel and choose from that menu. The result will be the same and the adjustment will be performed as an adjustment layer. Figure 5.1 Access the various adjustments, as well as presets for each adjustment, from the Adjustments panel. For Photoshop Elements Users: Adjustment Layers Elements users can find the available adjustment layers in the Layers panel, under the Create New Adjustment Layer . We have a couple more thoughts about layers. If you place a pixel layer on top of one or more adjustment layers, the adjustment layers don’t have any affect on that pixel layer because the adjustment layers are below it rather than above it. It’s like tak- ing another print and putting it on top of the stack—you’re going to see what’s on top, and what’s underneath is not going to affect what you see. For Photoshop Elements Users: Adjustment Layers Elements users can find the available adjustment layers in the Layers panel, under the Create New Adjustment Layer . 607343c05.indd 195 4/13/10 2:44:05 PM 196 c h a p t e r 5: WORKFLOWS AND FIRST STEPS ■ Now imagine you have a print with a great sunset, and you have another print with a silhouette of a group of birds flying by. If you took the print with the silhou- ette of the birds flying and placed it on top of the sunset picture, you’d see only the silhouette picture. But you could cut the birds out of that print and lay them on top of the print below. Now you’d see the sunset with the silhouetted birds flying through it. In Photoshop this is akin to having a pixel layer that is partially transparent (the part that you removed from the print is the transparent part) and partially filled with pixels (the silhouetted birds) resting on top of the original pixel layer—the sunset. The sunset is the background layer, and the layer with the birds is only partially filled with pixels. In other words, pixel layers can be partially transparent and partially filled with pixels. This is enough theory for now about layers, but we’ll be talking more about them later in this book. Take the time to reread this section again slowly if you’re feel- ing a little shaky about layers. Flexible and Traditional Workows The goal of all the adjustments in ACR is to create the best possible file from the data collected on the camera sensor when you took the picture. Although by now the image may look pretty good, there are some things you can’t do within ACR, such as apply filters, create composites, resize specific items, and sharpen output. And it’s possible you’ll want to tweak some of the exposure or color settings in parts of the image. We perform these tasks in a routine order to make the best final image possible. We’ll describe how to do the various modifications in Photoshop in detail beginning here and continuing through the next few chapters, but first we need to consider our workflow. Digital workflows are works in progress that evolve as technology and soft- ware change. With each new version of Photoshop, new features cause us to make major modifications to our workflow. For example, our workflow habits changed when adjustment layers became part of Photoshop (yes, there was a time when Photo- shop had no adjustment layers), they changed when it became easy to use adjustment layers on 16-bit files, and they changed yet again when converting raw files became easy, just to mention a few. With the arrival of CS3 we established a flexible workflow as our recommended workflow when optimizing an image in Photoshop for future use, particularly printing. The flexible workflow takes advantage of Smart Objects and Smart Filters to maintain the most editability along with the most nondestructive workflow possible. Ultimately this leads to the highest-quality files possible. However, there are times when you may have a specific output in mind and/ or need to make fewer changes and prefer to follow a more traditional workflow. We’ll describe both our flexible and traditional workflows in detail so you can choose what’s right for you. You’ll see that both these workflows are actually quite similar. 607343c05.indd 196 4/13/10 2:44:05 PM . flying through it. In Photoshop this is akin to having a pixel layer that is partially transparent (the part that you removed from the print is the transparent part) and partially filled with. background layer, and the layer with the birds is only partially filled with pixels. In other words, pixel layers can be partially transparent and partially filled with pixels. This is enough theory. each new version of Photoshop, new features cause us to make major modifications to our workflow. For example, our workflow habits changed when adjustment layers became part of Photoshop (yes, there