Photoshop cs5 cho nhiếp ảnh gia part 48 ppsx

293 ■ USING LAYER MASKS WITH COLOR ADJUSTMENTS Figure 7.16 Selective Color was used to improve the shade of blue in the sky by making it slightly warmer. Ph oto by Jo sh Ano n You will find that as you make a color more pure, there may be less need to increase overall saturation as much. This can lead to a more natural and pleasing final result in your image. To add a little extra “pop” to your pictures, select Black as your target color, and then increase the percentage of Black by a small amount, such as 2. The actual amount varies by image. This gives many images the illusion of being slightly sharper. You can use Selective Color to remove some stubborn color casts by choosing Neutrals in the Colors list and adjusting the sliders as needed. One of our students came to a workshop with a shot, taken under unusual lighting in a mausoleum, that had a strong cyan cast. The only method that was successful in removing the color cast was to virtually eliminate cyan from the Neutrals and Whites within Selective Color. Using Layer Masks with Color Adjustments So far we’ve described a variety of approaches for modifying the color within your entire image, all of which use adjustment layers and all of which adjust the color across the entire area of your photo. But there will be times when you want to target a spe- cific part of your image to change, a part that will be determined by the subject matter rather than by a particular color range. For example, you may want to increase the saturation of your subject more than the background to help draw attention to your subject. Of course you’ll use layer masks to do that. If you have any uncertainties about how to use layer masks, we urge you to take the time to refer back to the section “Tar- geting Adjustments with a Layer Mask” in Chapter 6. Remember that in CS5 and Ele- ments 8, the nonmodal adjustments make it easy to go back and forth fluidly between creating a layer mask and modifying an adjustment. Using layer masks gives you pre- cise control over the final appearance of your images. Layer masks work the same way for all adjustments. Let’s apply a mask to an image of a burrowing owl with a green background. (This image is called BurrowingOwl on www.sybex.com/go/photoshopnature.) To increase 607343c07.indd 293 4/13/10 2:41:53 PM 294 c h a p t e r 7: COLOR ADJUSTMENTS ■ the saturation of the colors within the owl, but not affect the background in order to help draw attention to the bird, take these steps: 1. Create a Hue/Saturation or Vibrance adjustment layer by clicking the icon in the Adjustments panel. 2. Increase the saturation to make the owl look good. Ignore what’s happening to the background. 3. In this case it’s easier to manually paint the layer mask rather than use a selec- tion method such as Color Range because the colors within the owl are quite similar to the background. Although we could begin with a white mask and paint out the background, it will be easier to begin with a black mask—hiding the effect of the layer—and then paint with white over the bird to reveal the effect on the bird. To quickly fill the layer mask with black, choose Edit > Fill from the menu, and choose Black for Contents. Note: A shortcut for filling a layer mask with black, if black is the current background color in the Color Picker, is Ctrl+Backspace/F+Delete. 4. Now use your Brush tool to paint on your image preview using white as your foreground color. As long as your adjustment layer is still selected, you are actu- ally painting on the layer mask and not the image itself. Paint with white over the bird to reveal the increased saturation only on the bird, as shown in Figure 7.17. 5. Next, modify the hue of the background using Selective Color. Create a new Selective Color adjustment layer (via the icon in the Layers panel), and label it Background Hue. 6. Modify the colors until they are pleasing. 7. To save the time of re-creating a mask to affect only the background, click the Hue/Saturation adjustment layer to make it active. 8. Hold down the Alt/Option key, click directly on the layer mask icon, and then drag it on top of the Selective Color adjustment layer. A dialog box appears ask- ing whether you want to replace the mask. Click Yes. 9. Unfortunately, this mask is the opposite of what you need, because you want to change the background on this layer. To invert the mask, go to the Mask panel and choose Invert. (Elements users will need to select the mask and then choose Filter > Adjustments > Invert instead.) The inverted mask enables you to modify the background without affecting the bird. Copying layer masks from layer to layer and inverting them as needed can be a time-saver. Note: If you’ve created a layer mask on one layer and want to further modify the same areas using another adjustment layer, Ctrl+click/F+click the layer mask icon in the first adjustment layer before creating the new adjustment layer. Photoshop creates an active selection based on that mask. Then when you open a new adjustment layer, the same mask appears. 607343c07.indd 294 4/13/10 2:41:54 PM 295 ■ USING LAYER MASKS WITH COLOR ADJUSTMENTS Figure 7.17 Filling with black allows you to quickly create a black layer mask; you’ll then paint with white on the mask to reveal the changes you made in that layer. Note: To copy a layer mask from one layer to another, hold down the Alt/Option key, click the layer mask you want to copy, and drag it to the one you want to replace. Using layer masks is easy and gives you incredible ability to fine-tune the color (and tonal values) within specific areas of your image. Regardless of which approach you prefer for creating your layer masks, being able to enhance parts of your image— such as the eyes of your subject—is invaluable. Arthur Morris, a world-renowned bird photographer, offers some thoughts on how he uses QuickMasks in conjunction with Photoshop adjustments to make his bird images even more compelling. Using QuickMasks is another way of making a selec- tion. Once you’ve created a QuickMask, any adjustment layer you create will reflect the selection. Of course, you can continue to modify the layer mask in all the tradi- tional ways we discussed in Chapter 6. 607343c07.indd 295 4/13/10 2:41:56 PM 296 c ha p te r 7: CO LOR ADJ USTME NT S ■ Digital Eye Doctor by Arthur Morris In The Art of Bird Photography, I wrote, “When viewing wildlife, or wildlife art, we tend to make immediate eye contact. Consequently, if a bird’s eye is in sharp focus, it gives the photograph an impression of overall sharpness.” While optimizing my images in Photoshop, I often have the chance to improve the look of a bird’s eye or eyes, and I have developed a useful bag of tricks for doing just that. Doing so can add greatly to the drama and impact of an image. For 99% of my eye repairs, I now use QuickMasks, which are simple to use and feature feather- ing equivalent to half the width of the brush. This results in seamless selective adjustments. To set up for quick masking, double-click the bottom icon in the toolbar . This brings up the Quick Mask Options dialog. In the Color Indicates section, choose Selected Areas. Then change the opacity to 80% and click OK. I stick with the default bright red color, but you can change it by clicking on the red box and selecting your new color. Now you are good to go. To toggle back and forth between RGB and QuickMask mode, press the keyboard shortcut Q. Let’s start with a simple task, darkening the pupil to increase apparent sharpness. First, make sure that you are on the Background or Smart Object layer. Then draw a small box around the eye with the Zoom tool so that the bird’s eye fills a good portion of the screen. Press Q to enter QuickMask mode and then press B for the Brush tool. Check to see that the hardness is set to 0. It’s best to use a brush that’s not larger than half the size of the pupil. Make sure that the fore- ground color is set to Black by pressing D. Now click and paint the pupil with the cursor. If you color outside the lines a bit, don’t worry. Press E for the Eraser tool and erase your mis- take. Press B to do more painting. Once you are happy with your paint job, press Q again to exit Quick Mask mode. Your selection will be outlined by the marching ants. Now open a Curves adjustment layer and drag the curve down a bit to darken the pupil. Do not overdo it as this will result in a black, plastic, cookie-cutter type eye. Once you go back to view the whole image, you can always reduce the effect by reducing the opacity of the Curves layer. When you use flash to photograph birds, the pupils are often rendered quite funky. Red-eye and steel-eye (an odd-looking silvery crescent on the eye) were common when using flash with film, but with digital (which is more sensitive to flash than film), the effects are both wider ranging and even more detrimental to the image. When you examine a flashed bird’s pupil (and sometimes the entire eye as well) at high magnification, unnatural highlights and lightened and artificially colored pupils are often revealed. Most folks simply ignore these problems, but the fix takes only minutes. Prepare a QuickMask of the pupil as above, but instead of making a Curves adjustment, make a Hue/Saturation adjustment. Slide the Saturation slider to the left to between –70 and –100, and then move the Lightness slider also to the left anywhere from –50 to –90. Reducing the saturation will eliminate the purples in the pupil and darkening it will make it look sharper. As earlier, be careful not to overdo it. Continues Digital Eye Doctor by Arthur Morris In The Art of Bird Photography, I wrote, “When viewing wildlife, or wildlife art, we tend to make immediate eye contact. Consequently, if a bird’s eye is in sharp focus, it gives the photograph an impression of overall sharpness.” While optimizing my images in Photoshop, I often have the chance to improve the look of a bird’s eye or eyes, and I have developed a useful bag of tricks for doing just that. Doing so can add greatly to the drama and impact of an image. For 99% of my eye repairs, I now use QuickMasks, which are simple to use and feature feather - ing equivalent to half the width of the brush. This results in seamless selective adjustments. To set up for quick masking, double-click the bottom icon in the toolbar . This brings up the Quick Mask Options dialog. In the Color Indicates section, choose Selected Areas. Then change the opacity to 80% and click OK. I stick with the default bright red color, but you can change it by clicking on the red box and selecting your new color. Now you are good to go. To toggle back and forth between RGB and QuickMask mode, press the keyboard shortcut Q. Let’s start with a simple task, darkening the pupil to increase apparent sharpness. First, make sure that you are on the Background or Smart Object layer. Then draw a small box around the eye with the Zoom tool so that the bird’s eye fills a good portion of the screen. Press Q to enter QuickMask mode and then press B for the Brush tool. Check to see that the hardness is set to 0. It’s best to use a brush that’s not larger than half the size of the pupil. Make sure that the fore - ground color is set to Black by pressing D. Now click and paint the pupil with the cursor. If you color outside the lines a bit, don’t worry. Press E for the Eraser tool and erase your mis - take. Press B to do more painting. Once you are happy with your paint job, press Q again to exit Quick Mask mode. Your selection will be outlined by the marching ants. Now open a Curves adjustment layer and drag the curve down a bit to darken the pupil. Do not overdo it as this will result in a black, plastic, cookie-cutter type eye. Once you go back to view the whole image, you can always reduce the effect by reducing the opacity of the Curves layer. When you use flash to photograph birds, the pupils are often rendered quite funky. Red-eye and steel-eye (an odd-looking silvery crescent on the eye) were common when using flash with film, but with digital (which is more sensitive to flash than film), the effects are both wider ranging and even more detrimental to the image. When you examine a flashed bird’s pupil (and sometimes the entire eye as well) at high magnification, unnatural highlights and lightened and artificially colored pupils are often revealed. Most folks simply ignore these problems, but the fix takes only minutes. Prepare a QuickMask of the pupil as above, but instead of making a Curves adjustment, make a Hue/Saturation adjustment. Slide the Saturation slider to the left to between –70 and –100, and then move the Lightness slider also to the left anywhere from –50 to –90. Reducing the saturation will eliminate the purples in the pupil and darkening it will make it look sharper. As earlier, be careful not to overdo it. Continues 607343c07.indd 296 4/13/10 2:41:56 PM 297 ■ US ING L AY ER M ASKS W IT H COL OR ADJ UST MEN TS Digital Eye Doctor (Continued) Though most photographers do not realize it, when we properly expose for a bird with white in its plumage, the middle tones are about a stop underexposed (and the blacks about two stops under). In addition, the eyes of many birds are rather deep-set. As a result, the irises, which often range from light gray to yellow to buff, are often well underexposed. To selectively lighten the iris, prepare a QuickMask as described earlier. Then make a Curves adjustment and drag the curve up a bit to lighten the iris. Toggle the eye icon to help you evaluate the changes that you have made. At times, a bird’s eye or eyes (or more often, the bird’s face or head) can use some selective sharpening even after you have darkened the pupil. Once again it is QuickMask to the rescue. Paint a QuickMask of the eye, the face, or the head as needed. Then press Ctrl+J/F+J to put your selection on its own layer. Then select Filter > Sharpen > Unsharp Mask and enter the fol- lowing values: Amount: 15, Radius: 65, and Threshold: 0 or 1. These are the basic settings that I start with when working with a contrast mask (which increases the apparent sharpness). Depending on the image, you can try anywhere from 10 to 30 for Amount and from 30 to 130 for Radius. Again, you can see the changes that you have made by clicking the eye icon off and on. When you are happy with the degree of sharpening, click OK. When you’re creating a contrast mask, the selected area is often darkened. At times this is beneficial to the image, but at times you will need to lighten the selected area. You can do this easily by making a Curve adjustment. Original After correction After correction Before correction If you’ve followed our workflow so far, you’ve cropped and rotated your image if necessary, removed any dust or scratches, made any necessary exposure adjust- ments, and modified the colors so that your image has the desired impact. Be sure to save your image at this point with your layers intact as your master file. The following chapters provide additional ideas of ways to create and present your images. Digital Eye Doctor (Continued) Though most photographers do not realize it, when we properly expose for a bird with white in its plumage, the middle tones are about a stop underexposed (and the blacks about two stops under). In addition, the eyes of many birds are rather deep-set. As a result, the irises, which often range from light gray to yellow to buff, are often well underexposed. To selectively lighten the iris, prepare a QuickMask as described earlier. Then make a Curves adjustment and drag the curve up a bit to lighten the iris. Toggle the eye icon to help you evaluate the changes that you have made. At times, a bird’s eye or eyes (or more often, the bird’s face or head) can use some selective sharpening even after you have darkened the pupil. Once again it is QuickMask to the rescue. Paint a QuickMask of the eye, the face, or the head as needed. Then press Ctrl+J/ F +J to put your selection on its own layer. Then select Filter > Sharpen > Unsharp Mask and enter the fol - lowing values: Amount: 15, Radius: 65, and Threshold: 0 or 1. These are the basic settings that I start with when working with a contrast mask (which increases the apparent sharpness). Depending on the image, you can try anywhere from 10 to 30 for Amount and from 30 to 130 for Radius. Again, you can see the changes that you have made by clicking the eye icon off and on. When you are happy with the degree of sharpening, click OK. When you’re creating a contrast mask, the selected area is often darkened. At times this is beneficial to the image, but at times you will need to lighten the selected area. You can do this easily by making a Curve adjustment. 607343c07.indd 297 4/13/10 2:42:00 PM 8 Ph oto by Jo sh Ano n 607343c08.indd 298 4/11/10 11:06:28 PM . be times when you want to target a spe- cific part of your image to change, a part that will be determined by the subject matter rather than by a particular color range. For example, you may. reveal the effect on the bird. To quickly fill the layer mask with black, choose Edit > Fill from the menu, and choose Black for Contents. Note: A shortcut for filling a layer mask with. on this layer. To invert the mask, go to the Mask panel and choose Invert. (Elements users will need to select the mask and then choose Filter > Adjustments > Invert instead.) The inverted