Compositing is often known by other names. You can call it combining pictures, or making a collage, or the art of photomontage. Whatever you call it, however, the goal is the same—to create one image from pieces of other ones—and for several reasons, Photoshop is the ideal program for this kind of work. First, Photoshop offers you all the tools you need to assemble pieces of different pictures. Second, it gives you the capability to place your image components on individual layers so you can manipulate them as much as you want before finalizing the image. Third, its filters, adjustment commands, and styles all enable you to blend pictures, add shadows and reflections, and integrate special effects more easily and effectively than any other graphics program on the market.
You can use the techniques described in this hour, along with all of the ones you’ve already learned, to produce all sorts of surrealistic images. For many people, this is what Photoshop is all about. For others, compositing is simply a great way to make up for deficiencies in the original picture. Either way, always keep an eye out for good sources of the components you’ll assemble to create composite images. These can be photos you’ve taken yourself, stock photos you’ve bought online or on a disc, or even photos you’ve downloaded from other people’s websites—if you have the photographers’ permission to use them.
When I saw a tiny police scooter in New Orleans’ French Quarter, I was completely charmed; it’s so very different from the police motorcycles we’re all used to seeing. So I shot a picture of it. Now, as I look at the image, it seems too static. There needs to be something living in the picture to liven it up. And, in my opinion, almost any photo can be improved with the addition of a greyhound or two. Clearly, the scooter picture needs a greyhound—so let’s make that happen. The two images I’ll be combining here are both available on the publisher’s website: nolascooter.jpg (see Figure 20.1) and oakley.jpg (see Figure 20.2). Feel free to download them and work along.
Select and copy Oakley, the greyhound, and then open the scooter picture and paste her in. Now, the easiest way to select Oakley is to select her white background with the Magic Wand. You’ll want to lower the tolerance to about 10 to make sure you don’t include any of her lighter-furred areas in the selection. Then invert the selection and feather it slightly, and you’re ready to copy. Figure 20.3 shows the image after Oakley has been transported to New Orleans.
After we’ve reduced Oakley to a more realistic size, using Edit, Transform, Scale, she still doesn’t look natural, but we can try a few tricks that should help that. First, she needs a shadow. If you look at the scooter, you’ll see that its shadow is almost directly under it (I must have taken this picture around lunchtime). So Oakley’s shadow needs to match that position, as well as the color. Figure 20.4 shows the image and the Layers panel so you can see the shadow I painted with a big soft brush using a color I picked up with the Eyedropper from the street under the scooter. I put the shadow on its own layer, so it wouldn’t cover up any part of Oakley, and I set the layer to 80% Opacity and Overlay blending mode. That ensures that the sidewalk shows through the shadow.
Tip: Controlling Transparency
It’s extremely simple to paste one opaque image over another one—just do it. Transparent objects such as shadows are more complicated to work with, which is why Photoshop gives you opacity controls. When you’re creating a multilayered picture, as in Figure 20.5, you can control the way the layers blend in two ways. One is by using the Opacity slider in the Layers panel. You can set any degree of opacity, from 100% all the way down to zero, at which point the contents of the layer completely disappear. You can also control how layers combine by using the Blending Mode pop-up menu at the top of the Layers panel. By applying different modes to different layers, you can control the way the colors in each layer overlay what’s underneath them.
There’s no way to determine which brush and Opacity settings to use, other than trying different ones to see what works best. The only things I could be sure of were the color and position of the shadow, because I could see where the shadows of other objects in the image were falling relative to the objects themselves. Experimenting with the other parameters gives you a chance to play with the shadow, to make it harder or softer, bigger or smaller, until it looks right.
Finally, a Levels adjustment on Oakley’s layer and then some burning along her front, along with a slight application of a warming photo filter, helps a lot to match the apparent lighting on the two layers. Figure 20.5 shows the finished photo. Oakley looks ready to hop right on the scooter and zoom off to find some gumbo and pralines.
Creating an image that’s not meant to be completely realistic is relatively easy. As you’ve seen so far in this hour, faking realism is a lot harder. The main tasks to consider in making composites are the following:
Isolating the elements on different layers for easier editing
Keeping the edges of pasted elements smooth so that they don’t stand out too much against the background
Making sure that the pieces you combine are in proper scale with each other
Matching the lighting and shadows in all the elements of a composite
Caution: Learning from the Real Expert
As you know, adding shadows, reflections, and other lighting-related special effects can make a big improvement in the final image. Watch out for perspective, too. If it’s wrong, you’ll know it, even when you can’t explain exactly why you’re not comfortable with the image. How can you get better at putting these elements together? The key is observation. When you’re walking around town or sitting in a well-lit room, notice where the shadows appear and how the light source affects the angle at which they fall from the objects causing them. Watch for reflections, too. When you understand how nature does it, you’ll be able to fake it more accurately in your images.
These become even more important when the elements in a composite don’t naturally belong together. When objects seem at home together, viewers are more likely to overlook glitches in lighting or scale. But when you’re putting things outside their normal milieu, viewers are already alert to the incongruity and will notice small discrepancies right away.
I’m a summer person; I love lush, green landscapes. One of the shots in my collection is just such a scene (see Figure 20.6). Let’s see what happens when we drop the scooter from downtown New Orleans into the middle of that wooded landscape. The scooter will definitely seem out of place, so we’ll have to work even harder than usual to make it look as though it’s really part of the original photo. This image, woods.jpg, is also available on the publisher’s website.
The first step is to extract the scooter from its background and then to bring it into the new setting. The scooter will probably need some color adjustments, but we’ll do those after it’s in place. I can do most of the selecting with the Quick Selection tool, but some cutouts will need extra work. For those, I’ll switch to Quick Mask mode and use the Brush and Eraser tools to refine the selection. Remember to zoom in when you have a complicated object to trace. As you can see clearly in Figure 20.7, it’s much easier to pick up the details when you zoom way in on the object you’re tracing.
Now let’s put the scooter in its new home. I can either copy and paste or just drag the selection from one image window to the other. Either way, the scooter comes in on a new layer, which is exactly where I want it. In Figure 20.8, I’ve dropped it into the woods, but it doesn’t look really at home yet.
As I analyze what’s wrong with this picture, I see several things. First, the scooter is too big; it needs to be scaled down to fit in with the young trees. Second, its angle is all wrong; the back wheel is poised up in the air. Then, of course, the whole thing is floating in front of everything instead of sitting on the ground. And the lighting is wrong; it doesn’t look as though it’s sitting under the same sun as the rest of the objects in the woods.
Let’s tackle the scooter’s size and angle first. I like to make quick fixes like this in Free Transform mode. Press Command-T (Mac) or Ctrl+T (Windows), and then click and drag a corner to resize the bike. Remember to press Shift as you drag, to preserve its proportions. Then click and drag anywhere outside the transform box to rotate the scooter to a more reasonable angle. Press Enter on the numeric keypad, or double-click inside the transform box, when you’re done. Figure 20.9 shows a close-up of the results of my transformation.
Now, what can we do to blend the scooter with its environment a bit more? I know—let’s park it behind that birch log instead of in front of it. Visual tricks like this go a long way toward convincing an onlooker that objects really belong where you’ve placed them. To reposition the scooter, use the Lasso tool to select the parts of the scooter that are in front of the log; then switch to the Background layer and choose Layer, New, Via Copy. This creates a new layer that contains just enough log to go in front of the scooter, so drag the new layer above the scooter layer. You’ll probably need to clean up the log layer a bit along the top of the log; when that’s done, the layer should look like Figure 20.10.
The final step is to adjust the brightness of the scooter so that its lighting matches the filtered, slightly dim light in the woods. Fortunately, the angle of the light in both images was similar. So all you need to do is switch to the Burn tool and pick a good-sized, soft-edged brush (mine is 150 pixels), and then set the Range to Highlights and the Exposure to 20%. Give the scooter a few swipes—make sure you’re on the right layer!— along its front, over the helmet, and on the seat pillar, where the highlights are a bit too bright. Now the little police scooter from the Big Easy looks right at home in the Granite State woods (see Figure 20.11).
Many times, the point of creating a composite image is to give something a different background, as I did by moving the scooter from a New Orleans street to the New Hampshire woods. Often the hardest part of the job is separating the object from its original background. The scooter was fairly easy to select because its shape was well defined against a fairly flat background, without a lot of picky details. Suppose we took something more difficult and moved it to the same scene. Consider, for instance, the organ grinder and his instrument pictured in Figure 20.12.
The Magic Wand won’t be much help here. I’ll begin by tracing loosely around the organ with the Polygonal Lasso and then inverting so that I can delete the outer edges of the picture. Figure 20.13 shows the lassoed organ; Figure 20.14 shows what’s left after removing the background.
You can get rid of the remaining edges around the cart in several ways. You can use the Eraser tool to remove the edges bit by bit. You can remove some small parts, but not many, by selecting them with the Magic Wand or the Quick Selection tool. But the easiest way is to use the Background Eraser. It’s behind the regular Eraser in the toolbox, and it’s designed specifically for this kind of work; it erases pixels to transparency as you drag it.
In Figure 20.15, I’ve erased most of the background. I used both the Background Eraser, as described, and the Magic Eraser, which determines where the chosen color ends and erases to the line of color change. (You choose the color by clicking it with the Magic Eraser.) The organ still needs a bit of cleaning up with the regular Eraser, though, particularly between the spokes in the wheels. After that, I’ll be able to slide it into position and rescale it, if necessary (see Figure 20.16).
So far, we’ve talked about the mechanics of combining multiple image elements into a single composition: selecting objects, positioning them on layers, and adjusting their appearance to make them seem to be parts of a whole. A good chunk of the time you’ll spend creating composite images is sheer work, removing backgrounds pixel by pixel and trying to match lighting in different elements. But Photoshop does have a few shortcuts to offer that can speed things up a bit.
If you’re working with an image in pieces—in other words, your images each show part of an element, such as the front of a house—Photoshop’s ability to automatically align and blend layers will amaze you. Take a look at Figure 20.17, for example. It shows two separate shots of a baseball field, each of which contains one side of the field. I’d like to put them together into a single image that shows the whole field, and that’s exactly what the Auto-Align Layers command can do.
The first step is to drag one of the images into the other’s window, making it a separate layer in the other image. You don’t have to worry about enlarging the canvas to hold it, or lining it up with the other image; Photoshop takes over from here. In the Layers panel, make sure both layers are selected; then choose Edit, Auto-Align Layers. (The command is grayed out unless more than one layer is selected.) Of course, you now have a choice to make; Photoshop can use any of several different methods to align the layers, and you need to pick one (see Figure 20.18). Or, if you’re lazy like me, you can just stick with the Auto setting and let Photoshop do the heavy thinking. If your picture is blurry around the edges, check the Vignette Removal box; if the picture was an extreme close-up or was taken with a wide-angle lens, check the Geometric Distortion box to fix any resulting geometric oddities by automatically transforming the image.
Click OK, and in short order you’re presented with a revamped image, with an enlarged canvas, if needed, in which the two (or more) layers are aligned perfectly (see Figure 20.19). They’re still individual layers, so you can hide and show each one a time or two to see how they fit together.
After that’s accomplished, the next job is to get rid of any pesky seams between the two images by blending the layers together. Once again, make sure the layers are selected in the Layers panel and choose Edit, Auto-Blend Layers. Here your choice is between two different Blend Method settings: Panorama and Stack Images. The former works better when there’s not much overlap among the layers; use the latter when the images you’re blending are just slightly different, as in Figure 20.20. Once again, Photoshop maintains the individual layers, using layer masks to control which layer contributes each part of the image. The result is a seamless image that incorporates the content of both pictures.
Compositing images involves a lot of transformations; you have to scale objects to fit together, and you might have to adjust perspective or even skew objects so that they work with the rest of the image. Every time you use a Transform command on a layer or selection, Photoshop reshuffles pixels to accommodate its new size and shape. If you do this enough times, you’ll end up with a blurry lump of pixels that doesn’t look much like the original object at all. Photoshop’s Smart Objects feature can prevent that from happening.
When you’re working with Smart Objects, Photoshop retains their original size and shape in the back of its mind, so to speak. Any changes you make appear onscreen, but they’re not made permanent until you rasterize the Smart Object or save it in a format that forces Photoshop to rasterize it. This means the pixels are reshuffled only once—to put the object into its final form, when you’re sure of how you want it to be. To make any layer into a Smart Object, just choose Layer, Smart Objects, Convert to Smart Object. After you’ve made the conversion, you can still move, transform, and apply filters to the layer. Only the Liquify, Lens Blur, and Vanishing Point filters can’t be applied to Smart Objects; all other filters turn into smart filters whose settings you can change by double-clicking their entries in the Layers panel (see Figure 20.21).
Tip: Links in a Chain
Another way to use Smart Objects is to open an image as a Smart Object (choose File, Open As Smart Object). This links the Smart Object to its original file; whenever the original is modified, the same changes appear in your linked version. This is a great trick for logos or other image elements that you drop into lots of other images.
Don’t overlook the power of Photoshop’s guides and gridlines when you’re assembling a composite image. You might think guides are useful only for type-heavy designs—not so! You can use them to line up elements in composites, as well as to make sure that your composition follows the traditional rule of thirds.
Smart guides are particularly useful, since they show up only when you need them. To turn them on, choose View, Show, Smart Guides. That’s all there is to it; with smart guides turned on, you’ll see a subtle pink guideline any time you move a layer near the edge or center of another layer’s content (see Figure 20.22). Let the layer snap to the guide to line up the objects, or ignore it completely—it’s up to you.
Regular guides are easy to add to your image; just choose View, Show, Rulers, and then click and drag out into the image from either ruler to create a guide parallel to that ruler. Move any existing guide by Command-clicking (Mac) or Ctrl+clicking (Windows) it and dragging it to a new position, or back to the ruler to delete it. For a screenful of guides in a convenient grid, choose View, Show, Grid.
You can also use Photoshop’s grid to help you comply with the rule of thirds, a centuries-old composition guideline for artists. The idea is simple: Divide the image into three rows and three columns, and keep strong horizontal or vertical lines near those lines, while placing the objects on which you want viewers to focus at their intersections. To create a rule-of-thirds grid in your images, press Command-K (Mac) or Ctrl+K (Windows) to open Photoshop’s preferences, and then click Guides, Grid, and Slices on the left. In the Grid area, set the Gridline Every value to 33.33% and the Subdivisions value to 1. Back in your image, choose View, Show, Grid to see the rule-of-thirds grid (see Figure 20.23).
People have been sticking photos together to create wider images—traditionally called panoramas—for close to a hundred years, with varying degrees of success. The theory is simple enough: Take a picture, then take another picture of what’s right next to it. Print the two and line ‘em up, and you’re all set. In life, however, things rarely work out that well. Even a slight difference in angle can make it impossible to match the two images manually, and you also have to deal with subtle differences in lighting and focus. Altogether, it’s really rather amazing that panorama artists have done as well as they have over the years. Wikipedia’s article on panoramic photography (http://en.wikipedia.org/wiki/Panoramic_photography) features some great examples of early and modern panoramas. These days, thanks to clever software, it’s easier than it’s ever been to get good results with panoramic photography.
Photomerge automates the process of assembling a panorama. After you’ve gone out and taken the photos, you plug your camera or memory card into the computer and download the pictures. Then you open Photoshop, bring up Photomerge, and tell it where to find the pictures you want to use. By the way, you’ll find the command hidden near the bottom of the File, Automate submenu. Figure 20.24 shows the dialog box. Click Browse and navigate to the folder that contains your individual images, and then choose the pictures you want to use to compose the panorama. If your panorama has some inconsistencies with brightness and contrast, try the Blend Images Together option. It blends together areas of color, while retaining detail. The effect is a softening of these differences, making the panorama seem more like a whole image rather than a collection of images. (It works the same way as the Auto-Blend Layers command.) Finally, choose a Layout option (the thumbnail images show you how each one handles your pictures) and then click OK.
When you click OK, the magic begins. First, Photoshop opens all the photos you specified and creates a new image file in which to assemble them. Then it arranges the images in order, matching the edges wherever they overlap (see Figure 20.25).
The Layout options in the Photomerge dialog box affect how Photoshop assembles your panorama. Most of the time, you’ll want to choose Auto, which lets Photoshop figure out the best way to put together the component photos. If you choose Perspective, Photoshop adjusts your images to try to compensate for the different angles at which they were taken. Cylindrical adjusts for perspective in a slightly different way that results in a more rectangular final image. Spherical is for images that originally appeared on a spherical surface, and Collage allows Photoshop to apply translation, rotation, or isotropic scaling as needed to match up the pieces of the panorama. Reposition doesn’t do any adjustment in size or shape—it just stitches the photos together.
It’s still up to you to crop the picture, if you want to. Some photographers argue that the slanting edges and unevenness of the “raw” panorama somehow add to the experience. Others, myself included, prefer to crop. A lot depends on whether, and how, you intend to print the picture.
Here are a few things to keep in mind when you head out to take pictures for a panoramic image:
Be sure you hold the camera steady at one height. Don’t take it away from your eye while you’re shooting. If you get interrupted in the middle, start over. If possible, use a tripod to keep the camera steady. Remember, digital photos don’t waste film, so you can take as many as you have room for on your storage media.
Don’t change the focus and zoom levels once you’ve started shooting.
Don’t use a flash, especially an automatic flash, which will throw varying amounts of light as it sees a need. These differences make the exposure all but impossible to correct. If your camera allows, turn off autoexposure and choose a suitable exposure value for the available light; you can try a couple of test shots and preview them on your LCD to check the value.
Use a normal lens, not a wide-angle lens, for best results. Set your zoom lens about halfway between zoom and telephoto, and leave it there. Wide-angle and fisheye lenses distort the focus, which precludes having everything in the same focus. And nothing distorts more than a fisheye lens.
Make sure you have a decent amount of overlap between pictures; around 20% is good. As you pan across the scene, remember what’s on the right side of each picture you take and be sure it’s included on the left of the next shot.
Take a picture of something clearly different between shooting panorama sequences, to help you keep groups of picture straight.
In this hour, we looked at the many Photoshop features that make it the best program around for creating composite images: its powerful layer capacities, a wide variety of filters and adjustments, and the capability to control opacity and layer-blending modes. You learned the principles of creating realistic composites, especially that matching both lighting and scale are key steps. We looked at compositing shortcuts, including the clever use of guides, automatic layer alignment and blending, and the use of Smart Objects to avoid resampling elements more than necessary. Finally, we covered the art of panorama photography and saw how Photoshop can make anyone into a panorama artist with a minimum of effort.
Pick out two of your own pictures or two stock photos—one a landscape and one a portrait of a person or animal. Remove the background from the portrait subject and transfer the subject in the landscape. Adjust the lighting as needed, and add shadows or reflections to make the person or beastie look as if he or she were actually photographed in that location.