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Color Insert
Color Plate 3-1: Taken from the Corbis Royalty Free image library, this photograph shows the effects of four different JPEG compression settings, starting with maximum quality, minimum compression (top) and ending with minimum quality, maximum compression (bottom). The images in the left-hand column show each compressed photo at the standard print resolution of 300 pixels per inch. Even with the Quality option set to Low (or a value of 3), the effects of lossy compression can be subtle and difficult to see, which is why I performed a few modifications to exaggerate the compression artifacts. First, because JPEG compression produces the most pronounced effects on highly saturated colors and super-sharp edges, I used Image Adjustments Hue/Saturation (discussed in Chapter 17) to recolor half the face a vivid blue and then applied Filter Sharpen Unsharp Mask (Chapter 10) to sharpen the focus. Second, because JPEG compression becomes easier to see at low resolutions, I magnified details from the original and colorized images to 200 percent (or 150 ppi) in the right-hand column. Throughout these examples, images toward the top of the page look better than those toward the bottom, but they likewise take up more room on disk.
Color Plate 4-1: One of the wonderful advantages of Photoshop's Lab mode is that it permits you to edit colors in an image independently of the brightness values. By way of demonstration, the top image shows an unedited photograph of a beluga whale. After converting the photo to Lab (Image Mode Lab Color), I switched to the "a" channel and pressed Ctrl+I (z -I on the Mac) to invert it. Because the "a" channel carries the green and pink colors in the image, inverting it swapped the greens inside the whale with pinks, as in the second example. In the third example, I started once again with the original Lab image, switched to the "b" channel, and chose Image Adjustments Auto Levels. This enhanced the contrast of the "b" channel, thus boosting the blues and yellows inside the beluga. In the final example, I combined the two effects, inverting the "a" channel and enhancing the "b" channel. Using some very simple commands, I was able to dramatically alter the colors in the image without harming a smidgen of detail.
Color Plate 4-2: Another way to wreak some pretty interesting havoc on colors without upsetting the detail in an image is to replace one color channel with another or swap the contents of two or more channels using Image Adjustments Channel Mixer. Starting with an RGB version of the beluga, I replaced the Red channel with the contents of the Green channel. The result of cloning the bright greens into the Red channel was to make the beluga yellow, as in the top example. Restoring the Red channel and cloning the Green channel into the Blue channel turns the whale vivid cyan, as in the second example. In the third example, I copied the contents of the Blue channel into the Red channel and vice versa, thus exaggerating the reds and muting the blues to almost nothing. In the final example, I swapped the contents of the Red and Green channels, which turned the previously greenish beluga a vivid magenta. Then I dimmed the Blue channel to 50 percent, leaving the whale a vivid orange.
Color Plate 5-1: Although the edit tools are less powerful than many of Photoshop's filters and color adjustment commands, they can be useful for applying spontaneous creative effects. In this sequence of images, for example, I added a mask to the woman's face shown at top using just two edit tools, the burn tool and the sponge. I started by selecting an area around the woman's eyes using the pen tool (which I discuss at length in Chapter 8). Then I painted inside the selection with the burn tool, toasting the skin to achieve a rich umber tone (middle). I painted additional strokes under the eyebrows and around the edges of the mask to deepen the shadows. Next, I painted inside the mask with the sponge tool to alternatively dim colors and saturate them. With the sponge set to Desaturate, I painted under the eyes, making the mask more gray. Then I changed the Mode setting to Saturate and painted over the forehead and the bridge of the nose, turning these areas a vivid orange. Finally, I deselected the image and painted inside the irises, lips, and hair to increase the saturation of these areas as well (bottom).
Color Plate 5-2: Looking at the top image on right, you might think, "Oh my goodness, she's a mess!" And wouldn't that be an unkind thought? But still, I have to admit, it's true. And it's all thanks to Photoshop CS's new color replacement tool. Left to its own devices, this tool either succeeds brilliantly or fails miserably. And in this case, the failure is utter and complete. For the record, I changed the foreground color to blue and painted inside the mask and lips. Then I switched the foreground color to orange and painted inside the eyes. And I painted carefully, too, not with a mouse but with a stylus and a super-accurate Wacom Intuos 2 Platinum 9 by 12-inch tablet. I'm a deft hand at this stuff and yet the result is about as bad as it can be. Which begs the question, does this tool suck or what? Between you and me, I haven't quite decided what I think of it. But for the present, I'm coming down on the side of "what." If you spend a little time, you can mitigate the response of the tool and make it behave a bit more to your liking. Here's how: First, change the Limits option to Find Edges. This forces the tool to resist painting beyond a ridge of high-contrast pixels until you lead with your cursor. This one change resolved the problems inside the eyes, as witnessed in the much improved lower example. To fix the lips, I followed up two or three applications of the color replacement tool with a bit of very careful history brushing. Then finally, I painted the mask with the Mode option set to Hue. This replaced the hue values while maintaining the original saturation and brightness.
Color Plate 5-3: These images show a series of brushstrokes applied using a handful of brush modes. In each case, I painted the lines with the brush tool. The lines are identical from one image to the next; only the mode and the Opacity setting change (as indicated by the labels). The bottom image gives you the best idea of what the brushstrokes themselves look like. Each of the six major groups of brush modes is represented. The default Normal mode produces an even mix of brushed color and underlying original pixel. At 30 percent Opacity, I got 30 percent brushed color mixed with 70 percent underlying (top). The next image shows an example of a darkening mode, Multiply, which causes the brush to burn and color at the same time. The image after that shows a lightening mode, Lighten, which applies a brushed color only when it's lighter than the underlying colors. Vivid Light darkens the darkest colors and lightens the lightest ones while enhancing color saturation. The Exclusion mode subtracts the brush colors from the underlying color values, in effect inverting as you paint. And finally, Luminosity preserves the brightness values of the brushed colors and mixes them with the colors from the pixels over which you paint.
Color Plate 6-1: Used properly, the paint bucket can be a powerful tool for coloring scanned line art like this 18th-century map (top). Start by creating an independent layer for each color in the image, as I did for New York, New Jersey, Connecticut, and the water. Next, select the paint bucket tool and turn on the All Layers check box in the Options bar. This allows you to fill one layer based on the contents of others. In filling my map, a Tolerance value of 120 seemed to work best. I selected the New York layer, set the foreground color to green, and clicked with the paint bucket until I had covered most of the state. Then I repeated the process for the other layers. The paint bucket cursors in the middle image show the locations of my clicks. Finally, I set each layer to the Multiply blend mode, which forced the fill colors to transition smoothly into the map. Even after clicking 20 or so times with the paint bucket, the image was not completely filled, as demonstrated by the gaps inside the mountain range (enlarged on right). So I used the brush tool to fill in these gaps where they appeared on each layer. Note that I didn't have to set the brush to any special mode — because Multiply was in force for each layer, Photoshop blended the colors automatically (bottom).
Color Plate 7-1: In creating a promotional piece for a training video (opposite page), I started with a simple digital photo of myself (top). I hadn't shaved, my lips were chapped, I wasn't wearing makeup — in short, I was a mess. So before I could begin work, I had to fix my face. I was hoping to eliminate the scaly bumps under my eye. I selected the healing brush, pressed Alt (Option on the Mac), and clicked in the shadow to the side of my nose, where the skin appeared smoother (middle left). Having set the source point, I began my brushstroke inside the shadow just below my eye. This ensured that the shadows from the source and destination areas aligned properly. By sampling texture and color independently, the healing brush fixed my scaly eye bumps in the first pass (middle right). For larger areas, give the patch tool a try. First, select the area that you want to fix, such as the lovely cluster of scars on my forehead (bottom left). I also feathered the selection slightly to soften the transitions. Then drag the selection outline over the texture you want to emulate (bottom right). The moment I released, Photoshop healed the scars using the texture from the new area and the colors that surrounded the selection outline.
Color Plate 7-2: Having healed a few of my most alarming facial defects — I'm not looking for sympathy or anything, I'm just saying, no tool can heal everything that's wrong with my mug — I set about building up some of the makeup I now regret I wasn't wearing. Because a nice duotone helps make even a troll look presentable, I colorized my face blue using Image Adjustments Hue/Saturation (discussed in Chapter 17). To give my skin a haunting glow, I used Select Color Range (Chapter 8) to select the highlights in the image. Then I feathered the selection and filled it with white, as shown on top. To complete the ad, I enlarged my eyes slightly, painted in new irises and pupils, painted away some of my beard, and drew a pacifier using the shape tools and a few layer effects (Chapter 14). The result is an image that makes me look remotely handsome. If I also happen to look a trifle insane, well, that's the price I pay. Anything for vanity, after all.
Color Plate 9-1: The top image shows an elliptical selection outline rotated a few degrees counterclockwise and feathered by a Radius value of 64 pixels. But you wouldn't know any feathering had occurred by the marching ants-style selection outline, which appears as hard-edged as ever. If you express the selection outline as a mask (middle), however, you can see it for what it really is — a feathered ellipse. White represents the selected area; black represents the deselected, or masked, area. From the Channels palette, you can choose to view any kind of mask — quick mask, layer mask, or independent alpha channel — by itself or along with the image. If you choose the latter, Photoshop shows you the mask as a traditional rubylith (bottom). Red-tinted areas are masked; untinted areas are unmasked, and thus represent selections. If an image already contains a preponderance of red, you can change the red overlay to any color you like.
Color Plate 9-2: Among other things, the quick mask mode affords you the option of feathering one portion of a selection independently of another. For example, let's say that I wanted to take this native African mask (upper left) and make it appear as if it were emerging from the ground like a giant totem. I began by selecting the mask using the pen tool and then switching to the quick mask mode by pressing the Q key. Then I drew a black-to-transparent gradient from the chin of the mask upward (upper right). This feathers the bottom of the selection while leaving the rest of it unharmed. I pressed Q again to switch out of the quick mask mode and Ctrl+C (z -C on the Mac) to copy the selection. I next switched to a different image that featured grassy plains against a clouded sky and pressed Ctrl+V (z -V) to paste the mask into its new background (lower left). Finally, I pressed Ctrl+T (z -T) to enter the Free Transform mode. Then I scaled and distorted the image by Ctrl-dragging (z -dragging) the corner handles (lower right).
Color Plate 9-3: What do you do when you want to composite a complex image — with hair and everything (top left) — against a new background? The solution is to create a complex mask. Using the technique outlined in the section "Building a Mask from an Image" in Chapter 9 — which hinges on Filter Other High Pass and Image Adjustments Levels — I arrived at the highly detailed mask shown above right. I used this mask to copy the girl and paste her against a new background. But while the edges were accurate, I still had a ways to go to make the composition look natural. I painted in colors from the background using the brush tool set to the Color mode. Finally, I used the brush tool set to Normal with the foreground color set to black to paint in a few very fine hairs. Here, it helped to have a Wacom pressure-sensitive drawing tablet. As it turns out, these painted hairs never occurred in the original image, but they helped sell the effect (bottom).
Color Plate 10-1: Arguably Photoshop's most useful filter, Unsharp Mask sharpens the focus of an image by increasing the contrast of edge details. You can apply the filter to an entire image or to independent color channels to achieve different effects. Starting with an image from the Corbis Royalty Free library (upper left), I applied Unsharp Mask with an Amount of 500 percent, a Radius of 4.0 pixels, and a Threshold of 0. The result is an exaggerated sharpening effect with very thick edges, creating the appearance of deep grooves in the cream on the woman's face (upper right). The remaining examples show what happens if I alternatively apply these same settings to a single color channel or a pair of channels. The results are relatively predictable once you understand what's going on. Unsharp Mask highlights edges by tracing light and dark lines along them. If you apply the filter in just the red channel, for example, the edges become red where Unsharp Mask traces its light lines and turquoise (the inverse of red) where the lines are dark. Beyond special effects, you can apply Unsharp Mask to independent channels to accommodate an image that has different focus problems in each channel (see Color Plate 10-3).
Color Plate 10-2: The Gaussian Blur filter ranks among Photoshop's most useful functions, essential for building masks, creating depth effects, and more. In the examples on left, I used Gaussian Blur to simulate a soft diffused glow. The first image shows the result of applying the filter with a Radius of 12 pixels. The image appears out of focus, as if in the background. The problem is, this woman is our foreground subject, so she needs to look sharp and clear. To bring back some of the detail, I chose Edit Fade and set the Mode to Darken, which kept only those pixels from the blur effect that were darker than their counterparts in the original image (middle). The result is an overall darkening of the image, with blurry transitions most evident in the highlights like the cheeks, eyes, and teeth. To restore some of the lightness to the image, I pressed Ctrl+F (z -F) to reapply the Gaussian Blur filter using the same Radius setting. Then I again chose Edit Fade, this time changing the Mode to Linear Dodge and reducing the Opacity value to 80 percent. The effect is one of an image shot in soft focus under powerful direct light (bottom), but with the pivotal details in the image fully intact.
Color Plate 10-3: This image I created for Macworld magazine more than ten years ago illustrates a common problem with scanned images. Where you see a continuous-tone image, your scanner sees and captures a collection of colored dots. If you commercially reproduce that scanned image — as I've done at top — you're adding new halftone to old halftone, which invariably produces moir patterns. How do you get rid of the halftone pattern without harming the image? The easy way is to apply the Dust & Scratches filter. But as demonstrated by the second image, in averaging away the pattern, Dust & Scratches has averaged away the detail in the image as well. The final image appears miraculous by comparison, and yet it's the result of about 10 minutes of work on the original scan. I used three filters — Median, Gaussian Blur, and Unsharp Mask — each applied to a single color channel at a time. As is typical, the blue channel was in the worst shape, so I applied the highest Radius amounts there. I was more careful with the green and red channels, which carry the majority of the detail and color information, respectively. For a full account of the procedure, read "Cleaning up scanned halftones" near the end of Chapter 10.
Color Plate 11-1: Most of Photoshop's Sketch filters — those that appear under the Filter Sketch submenu — recolor an image entirely in the foreground and background colors. (The exceptions are Chrome, which converts the image to shades of gray, and Water Paper, which retains the image's original colors.) For example, starting with the photograph shown at top, I set the foreground and background colors to medium green and light turquoise, respectively, and then applied Filter Sketch Halftone Pattern using the settings listed in the second image. The result is a photo that looks as if it were projected on an old-style computer monitor. That's fine, but what if you want to combine the texture from the filtered image with the colors from the original? Fade the filter. Immediately after applying the Halftone Pattern filter, I pressed Ctrl+Shift+F (z -Shift-F on the Mac) to invoke the Fade command and changed the blend mode to Overlay. Shown in the third image, the result brings back the reds and yellows inside the leaf but keeps the filtered greens inside the previously gray background. If you'd prefer to forsake all color from the filtered image, set the blend mode to Luminosity, as in the last example.
Color Plate 11-2: Here I've applied Filter Pixelate Mezzotint with the Type option set to Long Strokes to the photograph featured at the top of Color Plate 11-1. The left-hand column of images shows the results of applying the filter in each of the three main color modes, RGB, Lab, and CMYK. In each case, Photoshop has changed all pixels in each and every channel to either black or white, resulting in some very high-contrast images. To temper the effect slightly, I chose Edit Fade Mezzotint after the application of each filter and changed the Mode setting to Overlay and the Opacity value to 40 percent. As you can see in the right-hand column, fading Mezzotint permits me to achieve more subtle and functional effects.
Color Plate 11-3: At first glance, the Emboss filter may seem like one of Photoshop's most destructive commands. It takes a full-color image and makes it look as if it were chiseled out of a slab of neutral gray slate. But by virtue of its complete neutrality, it lends itself well to blend mode experimentations. The top example shows a satellite view of the Earth. Apply the Emboss filter with the settings listed in the second example, and details like earth and clouds are replaced with a swirling mass of engraved edges. The trick is, before applying Emboss, I floated the image to an independent layer. This way, I was free to experiment with the Opacity and blend mode settings. The third, fourth, and fifth examples illustrate the effects of different blend mode and Opacity combinations. Of the three, the Luminosity mode preserves the colors from the land and ocean, but chokes out the black sky and white clouds with gray. To fix this, I opened the Layer Style dialog box. Then I dragged and Alt-dragged (or Option-dragged) the triangles in the Underlying Layer slider bar to the settings listed in the final example, thus permitting the blacks and whites to show through. For more on the Underlying Layer slider, read "Dropping Out and Forcing Through" in Chapter 13.
Color Plate 11-4: One of my favorite things about Photoshop's distortion filters is that they permit you to create glittering op art, which I call synthetic effects, out of thin air. These particular synthetic effects are a result of the steps outlined in the "Twirling spirals" section of Chapter 11. Starting with the Blue, Red, Yellow predefined gradient, I applied the Twirl filter with an Angle value of –360 degrees. Then I pressed Ctrl+F (z -F on the Mac) twice to apply the filter a total of three times (upper left). Next, I cloned the image to a separate layer, chose Edit Transform Flip Horizontal, and applied the Difference blend mode (upper right). From there, it was largely a matter of cloning the layer and applying more transformations, as noted in the middle examples. Because the Difference mode remains in effect for each new layer, the bright colors from one layer invert the colors from the layers below, producing a wild array of colors that go well beyond the original blue, red, and yellow. To produce the final effect, I applied a series of filters to the top layer only. The specific filters and settings I used are listed in order in the figure. With its colorful bubbles and deeply etched concentric rings, the resulting image is perhaps the ultimate embodiment of groovy.
Color Plate 11-5: If I had to name the wackiest filter in all of Photoshop, after much pain and inner turmoil, I believe I would ultimately choose Filter Distort Polar Coordinates. Why? Because you can select the Polar to Rectangular option to tear a perfectly harmless image inside out. This can be especially useful for examining the composition of a spiraling effect, as in the top examples. Or if you're feeling ornery, try it out on a guy's face. As the second examples illustrate, the Polar to Rectangular setting makes a person's eyes slide down his cheeks and gives you a once-in-a-lifetime opportunity to look up his nose. But I guess my favorite use for this setting is to expand synthetic effects. The final example shows the Polar to Rectangular option applied to the final twirl drops image from Color Plate 11-4. Notice that the right side of each of the filtered images matches up perfectly with its left side. In the rainbow pool, for example, that subtle cyan splash flows from the right edge of the image into the left edge. This means the image will transition seamlessly when repeated horizontally, perfect for building patterns.
Color Plate 13-1: Simply put, blend modes permit you to mix colors and brightness values between independent layers. In the examples on right, I start with just two layers, a face painstakingly rendered by Michelangelo against a tranquil background. The face is set to the Normal blend mode and an Opacity value of 100 percent, so with the exception of some feathered edges, it is fully opaque. In the second image, I introduce three additional layers: an opaque black-to-white gradient behind the face, a 1946 vertical coil postage stamp directly above that, and the Blistered Paint pattern (one of Photoshop's presets) set to the Overlay blend mode and 30 percent Opacity at the very front of the stack. In the final image, I changed the gradient layer to the Screen mode and reduced the Opacity setting to 60 percent. Then I combined the face and stamp layers into a layer set and assigned the Luminosity blend mode to the set. By assigning the Luminosity mode to the set instead of the individual layers, I instructed Photoshop to blend the two layers as if they were one, so the face and stamp interact with other layers but not with each other.
Color Plate 13-2: Hungry for a fistful of yummy eye victuals? Then a Difference sandwich is sure to satisfy. Start with a flat image and press Ctrl+J (z -J on the Mac) to clone it to an independent layer. This new layer will serve as the meat of your sandwich. The meat holds the effect, so apply the filter of your choice. In my case, I was feeling rather famished, so I decided to fix three sandwiches. The top row shows my tray of meats, subject to three random filters — Unsharp Mask, Radial Blur, and Stamp. When you're finished filtering, select the Difference blend mode in the Layers palette. The middle row of images shows the effect of applying Difference to each of my meats. Now for the top slice of bread. Return to the original Background layer and press Ctrl+J (or z -J) to again clone it. Then press Ctrl+Shift+] (z -Shift-] on the Mac) to move the bread to the top of the stack. Now choose the Difference blend mode. That's all there is to it. In less time than it takes to say "baloney," I slapped together the bottom row of Difference sandwiches.
Color Plate 14-1: In addition to enabling you to define drop shadows and glows, layer effects let you devise libraries of graphic styles. They are, in fact, Photoshop's answer to parametric effects, which are forever editable formatting attributes painted on with numerical values. Consider the white 7 and black S in the upper-left image. I painted each on an independent layer using the brush tool. The layers have interesting shapes, but flat fills. So I set about applying layer effects. In the upper-right image, I applied a drop shadow and inner bevel to the 7 and an inner bevel and outer glow to the S. The middle-left image shows the effect of adding gradient and pattern overlays. To create the middle-right image, I added a satin effect to the 7 and color overlays to both the 7 and S with the blend mode set to Overlay. Next, I applied blend modes to the overall layers, but my settings had no effect. This is because the blend modes assigned to the interior effects take precedence over those assigned to the layers themselves. To change this, I double-clicked on each layer and turned on the Blend Interior Effects as Group check box. Now, all interior effects were governed by the layers' blend modes, as shown in the final image.
Color Plate 17-1: Here we see three sets of tricks pulled off by applying the Threshold command to independent color channels when working in the RGB (top row), Lab (middle), and CMYK (bottom) modes. The techniques are largely experimental, but they show you the kinds of high-contrast, graphic effects you can achieve using Threshold. The labels explain the specifics, but just so everything's crystal clear, I'll walk through one of the techniques: In the top row, I began by selecting the Green and Blue channels and choosing the Equalize command (upper left). Next, I clicked on the Red channel, applied the Median filter with a Radius of 2 pixels, the High Pass filter with a Radius of 3, and Threshold with a Threshold Level value of 122. Then I thickened the lines with the Minimum filter using a Radius of 1, and I smoothed out the edges by again applying Median with a Radius of 2 (upper middle). Finally, I switched to the Green channel, applied Median with a Radius of 6, and followed that with Threshold set to 126. I experimented quite a bit before arriving at these specific techniques. In the end, I was able to achieve vivid silk-screen effects, and with any luck, so will you.
Color Plate 17-2: Here we see the results of correcting the seemingly snooty Giuliano de' Medici as rendered by 15th-century master artist Sandro Botticelli, the same deft daddy-o responsible for The Birth of Venus, which later gained so much fame as the logo for Adobe Illustrator. In each case, I corrected the image using one of Photoshop's automatic adjustment operations: Auto Levels, Auto Contrast, and Auto Color, all under the Image Adjustments submenu. Auto Levels enhances the contrast of an image on a channel-by-channel basis, which may result in a color shift. In the case of good old Giuliano, the painting shifts from a green background to cool blue. If a color shift is not desired, use Auto Contrast instead. As the third image demonstrates, we now have sharper contrast, but the green background stays green. The Auto Color command seeks to neutralize the highlights, shadows, and midtones in an image, producing in the last example a gray background and perhaps the most naturalistic skin tones of the bunch. Rumor has it, Giuliano may have been painted posthumously. Perhaps his skin should be gray and the background a fleshy peach. Only my homey Sandro knows for sure.
Color Plate 17-3: The Hue/Saturation command permits you to shift the colors in an image or altogether replace them. By way of example, consider this image of me and my Little Puppet Friend (as played by my Photoshop Elements For Dummies coauthor, Galen Fott). In the upper-right example, I entered a Hue value of 120 degrees, which rotated the colors one-third the way around the rainbow, shifting the flesh tones to green, the puppet tones to pink, and so on. In the middle-left example, I performed the same Hue shift, but also increased the Saturation value to +40 percent, making the colors slightly more vivid. But let's say I wanted to alter the colors inside LPF only. Using the Edit pop-up menu, I adjusted the settings for the Cyans and Blues only — those colors that make up LPF's flesh — changing my buddy's skin from bluish to pinkish while leaving my own flesh unchanged (middle right). If you select the Colorize check box, Hue/Saturation replaces the colors in the image (lower left), but you can't limit the colorized areas as you can when Hue shifting. So if I wanted to colorize LPF's skin only (lower right), I would have to first select the cyans and blues using Select Color Range or the like, and then apply the Hue/Saturation command.
Color Plate 17-4: Young Sammy has grown a lot since the last edition of the Photoshop Bible. And we here at Team Bible are behind his growth 100 percent. But when a child's desire to progress in life comes at the expense of accurate color, we are less tolerant. Fortunately, we've seen enough of this kind of thing to blame the image, not the child. As luck would have it, I've had the foresight to open both a good-color Sammy (upper left) and a bad-color Sammy (upper right). Hence, I can match one to the other using Photoshop CS's new Match Color command. I start by making the bad-color image active and choosing Image Adjustments Match Color. Then I set the Source option to the good-color image and click OK. The result (lower left) looks different, but not better, and not that much like the source image. Obviously, Match Color is no miracle worker and must be pressed into compliance. So I undo the modification. Then I use the rectangular marquee tool to select a small swatch of the burgundy chair fabric in both the bad- and good-color images. These will help to focus the command's attention. I press Alt (Option on the Mac) as I choose Match Color to reload the Source image. Then I turn on the Ignore Selection When Applying Adjustment check box. This tells Photoshop to apply its change to the entire image. (The Image Statistics check boxes should remain on.) Finally, I turn up the Color Intensity setting to 125 and increase the Fade value to 50. The much improved image (lower right) is a testament to Sammy's flexible nature.
Color Plate 17-5: Sharpening or increasing the saturation values of an image can draw out JPEG compression artifacts. So correcting a heavily compressed photograph requires some extra work. I began with a washed out image that I shot several years ago with a Kodak DC50 digital camera (top). While the composition is nice, the focus is soft and the colors are drab. I copied the image to a new layer and boosted the saturation using Hue/Saturation. While the resulting image (second from top) is much more colorful, it's also rife with noise, grain, and rough edges. But that's okay. Because I have my original image in the Background layer, I can clear away the noise and still retain the clear edges I started with. I averaged the colors in the high-saturation layer by applying the Median filter. Because Median generates its own displaced edges, I followed up with Gaussian Blur (third image). Next, I mixed the filtered layer with the underlying original by selecting the Color blend mode. Lastly, I merged the layers and then enhanced the edges by applying Unsharp Mask. The final image is sharper than the original and more colorful, all without amplifying the JPEG compression artifacts (bottom).
Color Plate 17-6: If I were stranded on a desert island and had to pick one color adjustment command over all others — an unlikely scenario, but bear with me — it would be Image Adjustments Levels. The Levels command permits you to modify the black point, white point, and midtone, all independently, and on a channel-by-channel basis. This means you can fix brightness, contrast, and color balance from a central dialog box. Starting with the photograph shown at top, I modified the settings for the Red channel (second), Green channel (third), and Blue channel (fourth), according to the feedback provided to me by the histogram and the image preview. Finally, I returned to the RGB composite view and increased the gamma value to 1.40, which lightened the midtones. This increases the likelihood of the image printing successfully, without the shadowed areas filling in and becoming black.
Color Plate 17-7: The Gradient Map command maps brightness values in an image to colors inside a gradient, effectively turning an image into a kind of duotone, tritone, or better, depending on the number of colors inside the gradient. In the top row, I started with the classic Portrait of a Young Woman by 19th century Italian artist Pelagio Palagi. It's a wonderful composition, but that crazy Pelagio got the colors all wrong, so I decided to fix that by applying Image Adjustments Gradient Map and experimenting with two of Photoshop's predefined gradients: Violet, Orange and Chrome. The first of the two effects looks swell because the Violet, Orange gradient transitions evenly from first color to last. But Chrome is more elaborate, and therefore results in harsh edges when expressed as a map. So I decided to change my approach. Before applying the Gradient Map command, I copied the image to a new layer and then applied Gaussian Blur. Next, I experimented with applying each of three gradient maps, as shown in the second row. The results are blurry but smooth. To complete the effect, I mixed each of the mapped images with its underlying original by applying the Color blend mode (bottom row).
Color Plate 17-8: If you can't quite correct the colors in an image using Levels, try the Curves command, which permits you to adjust points on a brightness curve beyond the blacks, whites, and midtones. The left half of the top image shows the original uncorrected image; the right half shows the image after my Curves correction. After choosing Curves, I switched to the Green channel and lightened it by clicking at two points in the brightness graph and dragging up on the curve (second). Then I switched to the Blue channel, clicked at four points in the graph, and dragged the first point down to darken the darkest colors and the remaining three points up to lighten the lightest colors. The result was to increase the contrast of the channel (third). To complete the correction (upper right), I only needed to switch to the Red channel and lift the center of the curve slightly. But instead, I decided to finish things off with an arbitrary map. So I switched to the Red channel, added three points to the graph, dragged the first and last points up and the middle point down. This lightened the shadows and highlights while darkening the midtones, resulting in a couple of brightly colored red hats (bottom).
Color Plate 18-1: A duotone is an image created by blending two or more inks. But the term is also used to indicate any image created by blending colored inks, whether it contains a single ink (monotone), three inks (tritone), or four (quadtone). Printing two or more inks increases the dynamic range of an otherwise grayscale image, producing darker blacks and richer midtones. The examples on left show the process of building up a formerly grayscale image — scanned from an imperforate souvenir sheet of postage stamps issued in 1936 and captured nearly 70 years later with a Umax PowerLook 3000 desktop scanner — into first a Navy Blue monotone and finally a richly colored quadtone. Each example lists the new ink added to the mix. The swatches show the curve for the ink and the color of the ink when printed on its own. Notice that I have to adjust the curve for each ink every time I add a new one. The Navy Blue ink in particular declines radically as the inks build up. This prevents overinking or, since I'm ultimately printing to CMYK, overdarkening and ensures smooth transitions from one brightness value to the next.
