Tài liệu Photoshop cs5 by Dayley part 49 pdf

Part III: Selections, Layers, and Channels 332 FIGURE 10.31 The clipping mask used the spider as a template to cut out the jack-o-lantern image for spooky effect. Editing masks After a mask thumbnail has been placed in your Layers panel, you can edit it. You can edit the mask using the image, the channels, or the Masks panel. Edit a mask by painting on the image To edit the mask using the image, you must have the mask selected in the layer. Make sure the mask thumbnail has a white highlight around it, rather than the image thumbnail. This is some- times hard to see, so click back and forth a couple of times to see the difference. After you have selected the mask, you can use the Brush and Eraser tools to add to or subtract from the masked area. Using the Brush adds to the mask and using the Eraser subtracts from it. Use these tools directly on your image. The only difference you see is a change in the masks effects. Depending on what those changes are, this might not be the ideal way to edit your mask, because it is hard to be precise if the effects of the mask aren’t obvious. For instance, the mask in Figure 10.32 is placed over an exposure adjustment, and changes made to this mask simply lighten or darken the image a little, a hard change to see. Note Reducing the opacity on either the Brush or the Eraser tool paints levels of grayscale, creating a semi-permeable area of your mask. n Edit masks using the Channels panel A better option for editing this mask is to use the Channels panel. With the mask selected in the Layers panel, open the Channels panel, as shown in Figure 10.33. The channels panel contains the color channels found in your image, but it also contains any masks placed in your image. When you open the Channels panel, the mask channels are not visible. If you turn the visibility icon on, a rubylith mask appears in your image, reminiscent of the Quick Mask. Now as you make changes to the mask, you can see them clearly. 16_584743-ch10.indd 33216_584743-ch10.indd 332 5/3/10 10:25 AM5/3/10 10:25 AM Chapter 10: All about Layers 333 FIGURE 10.32 The white outline showing that the mask is selected means that I am making changes to the mask with the brush, rather than the image. If you would like to make changes to the mask all by itself, without a view of the image, you can deselect the visibility icon in the full color channel (RGB, in this example) and only the mask is vis- ible in your document window, as shown in Figure 10.33. FIGURE 10.33 You can edit the mask by itself by turning off the visibility of the color channels in the Channels panel. 16_584743-ch10.indd 33316_584743-ch10.indd 333 5/3/10 10:25 AM5/3/10 10:25 AM Part III: Selections, Layers, and Channels 334 Tip Layers and Channels are usually in the same tab group. If you are working with both simultaneously, however, it might be easier to undock one or the other and drag it out so both can be seen at the same time. n Editing masks using the Masks panel The Masks panel is the most comprehensive way to edit masks, not only giving you the option to add to or subtract from them but also allowing you to refine the edges, choose a color range, or invert it. You also can change your mask into a selection. Figure 10.34 shows the Masks panel. These options are available: FIGURE 10.34 The Masks panel Add Pixel Mask Add Vector Mask Load Selection from Mask Apply Mask Disable/Enable Mask l Mask thumbnail: The mask thumbnail shows you the currently selected mask as well as whether the mask is a pixel mask or a vector mask. l Add Pixel Mask: This button adds a pixel mask to the selected layer. If that layer contains an active selection, it is converted to the mask. l Add Vector Mask: This button adds a vector mask to the selected layer. If that layer con- tains an active path, the path is converted to the mask. 16_584743-ch10.indd 33416_584743-ch10.indd 334 5/3/10 10:25 AM5/3/10 10:25 AM Chapter 10: All about Layers 335 l Density: This slider adjusts the density or translucency of the mask. l Feather: This option adjusts the gradual translucency of the edges of the mask, creating a feathering effect. l Refine: l Mask Edge: This opens the Refine Edge dialog box (covered in Chapter 9) and allows you to make these changes to your mask. l Color Range: This allows you to apply your mask to a color range, similar to the Color Range dialog box discussed in Chapter 9. l Invert: This inverts the mask, selecting areas that were not previously selected and dese- lecting areas that were. Areas that are semitransparent also are inverted. l Load Selection from Mask: This option does not disable the mask, but allows you to make changes to it as if it were a selection. The marching ants appear on your image, and you can use selection tools to add to or subtract from the mask. You also can use the Quick Mask to paint in changes to the mask. l Apply Mask: Clicking this option combines a selected mask to the image, turning all masked areas into transparent pixels and deleting the mask. l Enable/Disable Mask: This “eye”con allows you to see the image as if no mask were applied. When the eye has a red line through it, the mask effects are not visible in the image. l The Masks panel menu: The Masks panel menu has options that allow you to add or subtract selections to or from your mask. You also can see the mask properties that allow you to change the color of the overlay and give names to your masks. Unlinking and moving masks To unlink a mask from its layer, simply click the link icon between the layer thumbnail and the mask thumbnail in the layer. When the mask is unlinked, it is no longer transformed with the image when it is resized or moved. You also can move masks from one layer to a different layer. You would probably do this if you wanted to create a selection in one layer, but use the mask in an entirely different layer. Let me show you what I mean. The first image in Figure 10.35 is a photo of some boys gathered around a table at the zoo. The second image is a cold baby giraffe that just wants a bit of hot chocolate. In order to create the photo composite you see in the last image in Figure 10.35, I had to create a mask on the layer con- taining the image of the boys and move it to the layer containing the image of the giraffe. On the Web Site Give this effect a try, or see my final results, by downloading Figure 10-35a, 10-35b, and 10-35c from the Web site. n 16_584743-ch10.indd 33516_584743-ch10.indd 335 5/3/10 10:25 AM5/3/10 10:25 AM Part III: Selections, Layers, and Channels 336 FIGURE 10.35 This baby giraffe just wants to join in the fun. Moving masks from one layer to another made this final image possible. I selected the grouchy boy in the foreground using the Quick Selection tool and then inverted the selection so the grouchy boy was the only thing that was deselected. After refining the edges, I exported this selection as a new layer with a mask. Now changes can be made to everything in this image except the grouchy boy. The problem is that I don’t actually want to make changes to this image; I just want to insert the giraffe in between the two boys on the left. The best way to do this is to place the mask I’ve just created on the giraffe, so the outline of the boy is cut out of the giraffe. First, I place the giraffe in the photo just where I want it, as shown in Figure 10.36. It is fairly obvious that it doesn’t belong to this image. I can fix that, though. By clicking and holding the mask thumbnail, I can drag it to the layer containing the giraffe, also shown in Figure 10.36, effec- tively masking the portion of the giraffe that I want to appear behind the boy, creating the effect that the giraffe is part of the picture. 16_584743-ch10.indd 33616_584743-ch10.indd 336 5/3/10 10:25 AM5/3/10 10:25 AM Chapter 10: All about Layers 337 FIGURE 10.36 Masks can be moved from one layer to another by clicking and dragging them. The Layer Comps Panel The Layer Comps panel is a way to take “pictures” of different layer arrangements in the same doc- ument. For instance, if I were creating a brochure and a flyer that had the same images and text but different layouts, I could make a layer comp for each in the same document. To create layer comps, follow these steps: 1. Create a layout in Photoshop. This layout is completely up to you. You can see an example of a flyer in Figure 10.37. 2. Open the Layer Comps panel. Choose Window ➪ Layer Comps. The panel is very simple and has few options. On the Web Site You can see how layer comps work by downloading Figure 10-37 from the Web site. n 16_584743-ch10.indd 33716_584743-ch10.indd 337 5/3/10 10:25 AM5/3/10 10:25 AM Part III: Selections, Layers, and Channels 338 FIGURE 10.37 The Layer Comps panel shows a layer comp for each of my designs. 3. Select the Create New Layer Comp icon to create a new layer comp. You can give it a custom name if you like. Layer properties such as position, visibility, and appearance are saved in this layer comp. 4. Make changes to the position, transparency, or appearance of your layers. These are the only changes that can be preserved in your layer comp, so resizing or delet- ing your layers is out of the question. 5. Select the New Layer Comp icon again, and save your new layer comp. You should have two layer comps in the dialog box shown in Figure 10.37. You can tog- gle back and forth between them by selecting the icon next to them to make them visible. Merging Layers When you have made your changes and you are sure that you don’t need separate layers any lon- ger, you can merge them. Not only does this clean up your Layers panel, but it reduces the size of 16_584743-ch10.indd 33816_584743-ch10.indd 338 5/3/10 10:25 AM5/3/10 10:25 AM Chapter 10: All about Layers 339 your file. Each layer you add makes the file bigger. You can see this in Figure 10.38; the two differ- ent file sizes listed in the document window are the document size with layers and the document size, respectively. FIGURE 10.38 The document window shows two sizes: the size of the document with layers added followed by the size of the original document. You can merge your layers in three ways: l Merge Layers: This option merges the selected layers. Use it when you want to merge some, but not all, of your layers. l Merge Visible: This option merges the layers that are visible, leaving any layers that have the Show/Hide Layer icon (the eye) turned off. l Flatten Image: This option flattens all the layers, leaving you with a background layer that contains the visible information of all the layers. After you’ve flattened your image, you can’t make changes to the individual elements that were contained in the layers; they are now part of the background layer. Summary Knowing how to use layers is an important part of being effective in Photoshop. This chapter cov- ered everything you need to know about the Layer menus, the Layers panel, and layers themselves. Although you may have some questions about the effects that can be added to the Layers panel, you should be able to add them, move them, and edit their settings. You have the skills to perform the following tasks: l Adding layers to your document in several different ways l Moving and editing those layers in your document as well as the Layers panel l Using Blending modes to effectively combine layers l Creating effects layers and understanding how they work l Creating layer masks to perform several different functions 16_584743-ch10.indd 33916_584743-ch10.indd 339 5/3/10 10:25 AM5/3/10 10:25 AM . edit the mask by itself by turning off the visibility of the color channels in the Channels panel. 16_584743-ch10.indd 33316_584743-ch10.indd 333 5/3/10 10:25 AM5/3/10 10:25 AM Part III: Selections,. were contained in the layers; they are now part of the background layer. Summary Knowing how to use layers is an important part of being effective in Photoshop. This chapter cov- ered everything. Site You can see how layer comps work by downloading Figure 10-37 from the Web site. n 16_584743-ch10.indd 33716_584743-ch10.indd 337 5/3/10 10:25 AM5/3/10 10:25 AM Part III: Selections, Layers, and