First, let's start with a technique that emulates the classic red filter with black and white film. I begin with both the desaturated image and color RGB image open in Photoshop, then:
1. Select the colored image, and open the Channels palette. Figure 8-20
2. Examine the red, green, and blue channels separately. Do this by selecting the layer of the channel you wish to examine. Figure 8-21 You should note how each color channel displays a grayscale version of the image, with slight variations depending on the channel.
As you can see in my example image, the Red channel contained a very dramatic sky. Figure 8-22 Since this was the effect I was looking for, I selected it. (Click on the image window, then used the keyboard command Cmd/Ctrl-A)
3. Make a copy of the Red channel image. (Cmd/Ctrl-C).
4. Next, paste a copy of the Red channel image into the grayscale version. Select the grayscale image, make sure the Layers palette is showing, and then paste (Edit > Paste or Cmd/Ctrl-V). You should see the red channel appear on its own layer above the Background layer. Figure 8-23
5. After pasting, create a Layer mask. First, select the pasted Layerin this case Layer 1. Click on the Layer mask icon found at the bottom of the layer palette.
6. Your layer palette should now look something like the one shown here. Figure 8-24
7. Now, select the mask by clicking on its icon in the Layer palette.
8. Fill the mask with black. Select Edit > Fill from the menu bar and use the settings shown here. This masks the entire contents of the top layer. Next you will paint and "reveal" only the parts you want to show through. Figure 8-25
9. Select the Brush tool from the tool bar. Choose an appropriate sized brush. (You can use the bracket keys to increase or decrease the size of the brush.) Figure 8-26
10. Make sure the foreground swatch at the bottom of the tool bar is set to white. (The keystroke X will switch background and foreground colors alternatively.) Figure 8-27
11. Make sure the layer mask is selected by clicking on it in the Layer palette. Then paint the areas you wish to reveal. (Lighter colors reveal. Darker colors mask). For more on using layer masks refer to Adobe's excellent online help. Figure 8-28 You can further control the effect by lowering the Opacity value either in the Brush tool options bar, or in the Layer palette.
When you are finished "painting" you can fine-tune the results by applying Levels or Curves to either or both layers, or simply call it a day. My final results are shown here. Figure 8-29 Note that I also used the red channel image to bring out the contrast of the tree on the left.
1. Select the colored image, and open the Channels palette. Figure 8-20
Figure 8-20.
2. Examine the red, green, and blue channels separately. Do this by selecting the layer of the channel you wish to examine. Figure 8-21 You should note how each color channel displays a grayscale version of the image, with slight variations depending on the channel.
Figure 8-21.
As you can see in my example image, the Red channel contained a very dramatic sky. Figure 8-22 Since this was the effect I was looking for, I selected it. (Click on the image window, then used the keyboard command Cmd/Ctrl-A)
Figure 8-22.
3. Make a copy of the Red channel image. (Cmd/Ctrl-C).
4. Next, paste a copy of the Red channel image into the grayscale version. Select the grayscale image, make sure the Layers palette is showing, and then paste (Edit > Paste or Cmd/Ctrl-V). You should see the red channel appear on its own layer above the Background layer. Figure 8-23
Figure 8-23.
5. After pasting, create a Layer mask. First, select the pasted Layerin this case Layer 1. Click on the Layer mask icon found at the bottom of the layer palette.
6. Your layer palette should now look something like the one shown here. Figure 8-24
Figure 8-24.
7. Now, select the mask by clicking on its icon in the Layer palette.
8. Fill the mask with black. Select Edit > Fill from the menu bar and use the settings shown here. This masks the entire contents of the top layer. Next you will paint and "reveal" only the parts you want to show through. Figure 8-25
Figure 8-25.
9. Select the Brush tool from the tool bar. Choose an appropriate sized brush. (You can use the bracket keys to increase or decrease the size of the brush.) Figure 8-26
Figure 8-26.
10. Make sure the foreground swatch at the bottom of the tool bar is set to white. (The keystroke X will switch background and foreground colors alternatively.) Figure 8-27
Figure 8-27.
11. Make sure the layer mask is selected by clicking on it in the Layer palette. Then paint the areas you wish to reveal. (Lighter colors reveal. Darker colors mask). For more on using layer masks refer to Adobe's excellent online help. Figure 8-28 You can further control the effect by lowering the Opacity value either in the Brush tool options bar, or in the Layer palette.
Figure 8-28.
When you are finished "painting" you can fine-tune the results by applying Levels or Curves to either or both layers, or simply call it a day. My final results are shown here. Figure 8-29 Note that I also used the red channel image to bring out the contrast of the tree on the left.
Figure 8-29.
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