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ptg Adjustments in Depth 217 A Color Balance adjustment layer can be used to apply a warm or cool cast to an image or, con- versely, to neutralize an unwanted cast. e three Tone choices of Shadows, Midtones, and Highlights let you restrict the adjustments to a specic tonal range, and each slider aects a pair of cool and warm colors. Note: If you need to pinpoint color adjustments to an even narrower range, use Curves or Hue/Saturation. To make an image cooler or warmer using a Color Balance adjustment layer: 1. Click a layer or the Background. A 2. On the Adjustments panel, click the Color Balance button. 3. For Tone, click the range to be adjusted: Shadows, Midtones, or High lights. Optional: Keep Preserve Lumi nosity checked to preserve the tonal values of the layer as you make corrections. Or uncheck this option to apply soft color adjustments to highlights, such as to skin tones. 4. Each slider pairs a cool color with a warm one. Move a slider toward any color you want to add more of or away from any color you want to reduce B–C (also A–B , next page). For exam- ple, you would move a slider toward green to subtract magenta, or toward yellow to reduce blue. Watch how the overall image changes as you add or reduce a particular color. ➤ To make the image warmer or cooler, move multiple sliders toward similar colors. For example, to add a cool cast, you could move the rst slider toward Cyan and the third one toward Blue. Or to make an image warmer, move the rst slider toward Red and the third one toward Yellow. 5. Click any other Tone button, then adjust the color sliders for that range. You can click the visibility icon to compare the adjusted image with the original. A i s i m a g e h a s a c o o l b l u e c a s t . C e s h a d o w a r e a s l o o k m o r e n e u t r a l t h a n before, but further corrections are needed. See also the figures on the following page B We clicked the Shadows range for our Color Balance adjust- ment layer, then moved the sliders toward Red, Green, and Yellow to neutralize the shadows. Applying a Color Balance adjustment ptg 218 Chapter 13 A To neutralize the blue cast in the midtones, we clicked Tone: Midtones, then moved the sliders toward Red and Yellow. A blue cast in the highlights remains to be xed. B To warm the highlights and neutralize the remaining traces of the blue cast, we clicked Tone: Highlights, then moved the sliders toward Red and Yellow (and also slightly toward Magenta). Now the food and the plate look warmer (and more appetizing!) and the shadows are more neutral. ptg Adjustments in Depth 219 For making precise hue and saturation corrections without having to make a selection, try using a Hue/Saturation adjustment layer. With the Hue/ Saturation controls, you can target specic colors, then shift just those colors to a dierent hue or adjust their saturation or lightness. is is a useful way to swap out colors in a product or fashion shot. To use a Hue/Saturation adjustment layer for color correction: 1. Click a layer. A 2. On the Adjustments panel, click the Hue/ Saturation button. 3. Do any of the following: To correct all the colors in the image, keep Master as the choice on the second menu. Move the Hue slider to adjust all the hues, the Saturation slider to adjust their color intensity, or the Lightness slider to lighten or darken them. After adjusting the Lightness, you may need to increase the Saturation to revive any colors that became too light or dark. To change the hue of a specic color, B click the Targeted Adjustment tool on the panel, then Ctrl-drag/Cmd-drag horizontally over that color in the image. C e color range you drag over is now listed on the menu, and the adjustment slider shifts to that color on the color bar. Or to change the saturation of a spe- cic color, drag horizontally with the Targeted Adjustment tool over that color in the image without holding down Ctrl/Cmd. A We will change the blue napkin on the right side of this image to yellow, to coordinate better with the lemons on the left. C Now the napkin is yellow. B We created a Hue/Saturation adjustment layer, then clicked the Targeted Adjustment tool. Holding down Ctrl/Cmd, we dragged over the blue of the napkin until the hue shifted into the yellow range. Finally, we increased the Saturation and reduced the Lightness for the adjusted colors. Changes to the sliders are reected in the lower color bar Applying a Hue/Saturation adjustment ptg 220 Chapter 13 Applying an Auto Color Correction e Auto Color Correction Options dialog oers a choice of three preset algorithms (formulas) for adjusting the color and contrast in an image, and in addition, it lets you correct the luminosity and color temperature of the midtones. To apply an Auto Color Correction: 1. Open an image. A 2. On the Adjustments panel, click the Levels button, then hold down Alt/Option and click Options (the Auto button becomes Options). 3. e Auto Color Correction Options dialog opens. B Move it, if necessary, so it’s not blocking the Levels histogram, which you should monitor as you choose options. 4. Click the Find Dark & Light Colors algorithm (see the sidebar on the next page). C We clicked the Midtones swatch to open this dialog, then chose a medium brown to neutralize the color temperature of the sand. B In the Auto Color Correction Options dialog, we clicked Find Dark & Light Colors and checked Snap Neutral Midtones. A e m i d t o n e s i n t h e o r i g i n a l i m a g e h a v e a m a g e n t a c a s t , w h i c h is noticeable in the sand. 5. Check Snap Neutral Midtones. Any colors that are close to neutral will be adjusted to match the Midtones target color swatch in the dialog. 6. To adjust the color temperature of the image, you can assign a subtle color tint to the mid- tones. Click the Midtones swatch. e Select Target Midtone Color picker opens. C Click the H button in the HSB group, then drag the circle in the large square slightly to the right (keep the S value around 10–30). Next, on the vertical Hue bar, click a reddish-yellow hue to make the overall temperature of your image warmer, or a greenish-blue hue to cool it down. To adjust the brightness of the midtones, drag the circle slightly upward or downward (keep the B value around 45–55). ptg Adjustments in Depth 221 Note: Midtones is the only swatch you need to change; the other two swatches will be adjusted automatically when the le is prepared for printing. 7. Click OK to exit the Select Target Midtone Color dialog, then again to exit the Auto Color Correction Options dialog. A When the alert dialog appears, oering you the option to save the new target colors as defaults, click No (we would rather choose settings on a case- by-case basis than establish global default settings). THE AUTO COLOR CORRECTION ALGORITHMS ➤ Enhance Monochromatic Contrast moves the black and white Input Levels sliders inward to enhance con- trast. The sliders are moved the same amount for each channel, to preserve color relationships. (The Image > Auto Contrast command also uses this algorithm.) ➤ Enhance Per Channel Contrast moves the Input Levels sliders inward by a different amount for each channel, and produces more noticeable color shifts and changes in contrast than the other algorithms. (The Image > Auto Tone command also uses this algorithm.) ➤ Find Dark & Light Colors (our favorite algorithm) positions the black and white Input Levels sliders in each channel based on the average darkest and lightest pixels in the image, and enhances the contrast. (The Image > Auto Color command also uses this algorithm.) B By comparison, clicking in the original image with the gray eyedropper in Levels (in the location shown above) failed to remove the magenta cast from the midtones. A e a d j u s t m e n t s m a d e to the midtones via the Snap Neutral Midtones and Target Colors options in the Auto Color Correction Options dialog successfully removed the magenta cast. ➤ e Auto Color Correction Options dialog also opens when you Alt-click/Option-click the Auto button for a Curves adjustment layer. ➤ You could also adjust the midtones by clicking a neutral gray area in the image with the gray point (middle) eyedropper in Levels or Curves, but this method is less reliable because it only works if you click in the right spot, which isn’t as easy as it sounds. B . magenta, or toward yellow to reduce blue. Watch how the overall image changes as you add or reduce a particular color. ➤ To make the image warmer or cooler, move multiple sliders toward similar colors.
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