Professional Information Technology-Programming Book part 41 ppt

to the new car so that we'd be shooting it from the same distance and angle and at approximately the same time of day. The end result was so believable that the agency simply paid for the finished product and ran the ads pretty much as they were shot and processed. We also ended up getting several other assignments from the same agency for fashion shoots in which the desired location was too remote to make it affordable to send an entire crew and group of models there. If you simply can't do all that, at least you can do some perspective matching by using either one of two Photoshop toolsFree Transform and Lens Correction filter. You can also match the perspective of flat or nearly flat objects such as floor tiles, mirrors, pictures, or grass by using the Vanishing Point filter. 9.4.4.1. Matching perspective with Free Transform The Free Transform command (Cmd/Ctrl-T) is the easy way to give perspective to a flat object on a layer. I find it especially useful for playing a very simple trick: simulating a seamless background when there was no studio handy. The photograph of Kashi Stone modeling one of her famous outfits was photographed outdoors on a grassy Marin County hillside. Later, we did a series of shoots on white backdrops, but Kashi was too busy sewing and fitting models to take part. So I used the Extract filter to knock her out. Then I did the following: 1. Created a new, empty layer beneath the Knockout layer. 2. Made a rectangular selection and feathered it by 70 pixels so that it would gradiate from white to gray to white. I filled the rectangle with light gray then dragged the selection to the next position (making sure the New Selection Icon was selected in the Options bar) with the Rectangular Selection tool and filled it again until I had what looked like a striped background or curtain (see Figure 9-21). Figure 9-21. You can see how the selection rectangle feathers and how the Transform marquee takes it into account. A variation on this technique could also be done with Vanishing Point. 3. Once all the stripes were made, I made a new Rectangular selection that covered the bottom portion of the image. I then feathered that selection by 100 pixels so that the stripes would "bend" when I transformed the rectangle to make a perspective transformation. To make this transformation, you will need some space all around the image. Double-click the Hand tool to fill the screen with the image window. Choose the Zoom tool, press Opt/Alt and click in the center of the image. Each time you click, the image will become progressively smaller until you have all the room you need. You can also drag the corner of the window so you have more room from side to side. 4. To make the perspective transformation, all I needed to do was press Cmd/Ctrl-T, then press Cmd/Ctrl and drag each of the corner rectangles directly out to the side and equidistant from the original position. 5. I wanted to "light" the background so that Kashi actually looked like she was standing there and so that the part of the background that was on the floor was slightly darker. I created a new layer above the background layer, made another feathered rectangular selection, filled it with a light gray, and then used the Multiply Blend Mode so that the layer below would show through. NOTE An excellent way to make non-seamless walls and floors is to use the Patch tool. Just make a selection around the edges that should be seamless and then move it onto the floor. This technique works best when the patterns in the floor and wall aren't too pronounced or too different from one another. 6. I needed to "anchor" Kashi with a shadow. I made a new layer, made a freehand selection under her feet, feathered it by 120 pixels, and filled it with a 35 percent gray. I then changed that layer to Multiply mode. I also used Free Transform to stretch the right side of the shadow so that it was cast further to the right than to the left. Finally, I used the Burn tool to really darken the areas immediately under her foot and the coat. 9.4.4.2. Lens Correction filter This filter is discussed a bit more in the "Lens correction" section in Chapter 8. It's perfect for correcting any tilts you might have forgotten to correct in Camera Raw, for getting rid of vignettes and lens distortion, and for correcting the overall perspective. I particularly like the way it lets you correct perspective by rotating the image both left and right and top to bottom, which allows you to visually fine- tune the results. Another use is for creating backdrops. In Figure 9-22, I created a wall on one layer and the floor on another and used the Lens Correction filter to position the wall and floor in separate operations. Figure 9-22. The back wall and the floor were from separate photographs and perspective-corrected with the lens distortion filter. The floor then needed further perspective correction using Free Transform. 9.4.4.3. Vanishing Point filter Vanishing Point is one of the coolest new features in Photoshop CS2. It is especially useful for architectural photography and cleaning up flat surfaces. It is also great at letting you redecorate by adding new doors, windows, or paintingsall in perfect perspective. Figure 9-23 shows the before and after of one such situation. Pay attention to the workflow, this feature is anything but intuitive. Figure 9-24 shows you the images I started with and the image I ended with. Obviously, I was just fooling around to make a point. I'll leave it up to you to do the serious stuff. Figure 9-23. On the right, you see this alleyway as it has been "bricked" in Vanishing Point. Figure 9-24. The image in the Vanishing Point interface. Vanishing Point works by having you set a perspective grid for all the flat surfaces in your image into which you're going to place perspective.  If you want to do that according to the workflow laws set by yours truly, first duplicate and flatten the background image. If you don't do that, you'll find this process unrecoverably destructive.  Minimize the destruction by putting the Vanishing Point stuff on its own layer. So as soon as you've duplicated and flattened the image (and closed the original image so you don't accidentally overwrite it), open the Layers palette and click the New Layer icon. A new blank layer will appear.  If you're going to "perspectivize" an image from an outside source, open it, duplicate it, then flatten and re-size the duplicate so that it's close to being the size in the final image. Also, if that object is a flat object (that's the only kind that will work) that was photographed from an angle, use Lens Correction to correct its perspective. Once you've done all that, press Cmd/Ctrl-A to select all, Cmd/Ctrl-C to copy it to the clipboard.  If your target image will use outside images in this effect, you'll have to open them in a separate window, select the portion of the image you want to use, and copy it to the clipboard (Cmd/Ctrl-C). Be sure you don't do anything to replace that image in the clipboard before you're ready to use it. Just in case you do, keep that image open so that you can repeat pasting it to the clipboard if you need to. Whew! Alrighty! We're finally actually ready to use Vanishing Point. Make sure the new layer is the one selected, not the background layer. What you see should be the background image, the Layers palette and the image you're going to use to surface a portion of the background image. 1. Open the image you're going to use on the surface of the background image. Press Cmd/Ctrl-C to copy it to the clipboard. 2. Choose Filter Vanishing Point. You'll see the image in the Vanishing Point interface, shown in Figure 9-24, except the perspective grid won't be in place. 3. Choose the Create Plane tool in the toolbox. It looks like a perspective grid. You're going to draw a perspective grid that looks like the one in Figure 9- 25. Click to set the first point, drag to set the next corner, then the next. In this image, I used the four corners of the window to keep the perspective correct. If you make a mistake, do not press Esc! It'll just drop everything you've done up to that point and return you to the original image. Figure 9-25. The bricked wall. 4. If you've laid out the original plane properly, it'll be blue. If it's not geometrically correct, it'll be red. Use the Edit Plane tool (arrow) to move the corner points until the grid is suddenly blue. 5. Stretch the grid up the gray wall on the right. Just grab the center right handle and pull it up the wall. When you get to the edge of the image, change the direction of the grid to lie flat along the white part of the image that contains the incoming picture(s). Then, go back and stretch the bottom of the grid straight out until it reaches the bottom of the image. 6. Press Cmd/Ctrl-V once the Grid is in place. The image you're using to resurface your image will appear. Be sure to place it in an area of the image that you're not resurfacing. The image will be selected as soon as you paste it. Press Opt/Alt and drag the contents of the selection onto the perspective grid. As soon as you do, the image will transform itself to the correct perspective, regardless of which plane you drag it to. 7. Be sure to keep the Marquis tool selected. This time, make sure you've chosen On from the Heal menu. Place the cursor inside the selection and press Opt/Alt again and immediately drag your surface image to the next location. Keep repeating this step until your entire grid is filled. In this image, I've created a brick wall and driveway. You can see the result in Figure 9-25. Click the OK button and you will return to Photoshop. 8. Now choose Select Load Selection Whatever You Named Your Mask. When the selection appears, go to the Layers palette and click the Mask icon. The original windows and the vegetation that was growing along the intersection of the walls will all reappear. 9.4.5. Matching Size When you composite one photograph into another, the image(s) added to the background image should always be at the same resolution per inch as the background imageor higher. You may be able to get away with images that are slightly too small, but otherwise the image is going to lack detail and contain too much noise. Figure 9-26 shows you a background image with an incoming knockout superimposed on it in a new layer on the left, after resizing but before sharpening and noise matching. On the right, you see how the image looks after it's been resized and the noise level reduced. Figure 9-26. The truck on the right looks like it's been here all along, thanks to noise matching, color balancing, sharpening, and shadow casting. Because you often have to downsize composited objects to give them the right scale in regards to their location in the background, you'll probably lose much or all of the noise (the equivalent of grain in film) that was originally in the image. Always do this when the object is on a separate layer from the background. It's also a very good idea to duplicate the original layer and then hide it beneath the background layer. Then, if you're asked to add more or less noise, you can delete the layer to which you added the noise, pull duplicate the original layer, and make a change. No need to search around to find the original, re-do the color matching, etc. After you've transformed the image down to the size where it fits realistically into the composition, you will generally need to do two things: match image noise and re-sharpen. Both should be done with tools that let you see both the knockout and the background superimposed over one another and should have a preview option so that you can match sharpness and noise visually. NOTE If you have multiple images that need to be added in and resized, you may be able to save disk space by pasting one or more of the originals onto a transparent layer. Then, should you need to remanipulate one of the originals, you can simply select that one subject and lift it to a new layer with our workflow's most useful shortcut . series of shoots on white backdrops, but Kashi was too busy sewing and fitting models to take part. So I used the Extract filter to knock her out. Then I did the following: 1. Created a new,. "light" the background so that Kashi actually looked like she was standing there and so that the part of the background that was on the floor was slightly darker. I created a new layer above the. for getting rid of vignettes and lens distortion, and for correcting the overall perspective. I particularly like the way it lets you correct perspective by rotating the image both left and right