Adobe Photoshop CS3 - Manual (Page 174)

PHOTOSHOP CS3
User Guide
167
Keyboard shortcuts: Curves dialog box
You can use these keyboard shortcuts in the Curves dialog box:
• To set a point on the curve in the current channel specified in the Curves dialog box, Ctrl-click (Windows) or
Command-click (Mac OS) in the image.
• To set a point on the curve for the selected color in each color component channel (but not in the composite
channel), Shift+Ctrl-click (Windows) or Shift+Command-click (Mac OS) in the image.
• To select multiple points, Shift-click points on the curve. Selected points are filled with black.
• To deselect all points on the curve, click in the grid, or press Ctrl-D (Windows) or Command-D (Mac OS).
• To move selected points on the curve, press the arrow keys.
• To move forward through control points on the curve, press the right arrow key.
• To move backward through control points on the curve, press the left arrow key.
Color correct using the eyedroppers
You can use the eyedroppers in the Levels or Curves dialog boxes to correct a color cast—an unwanted tint from an
excess of color (red, green, blue, or cyan, magenta, yellow). It’s easier to color-balance an image by first identifying
an area that should be neutral and then removing the color cast from that area. Depending on the image, you may
want to use one or all three of the eyedroppers. The eyedroppers work best on an image with easily identified
neutrals.
Note: The Set Gray Point Eyedropper tool is used primarily for color correction and is unavailable when you work
with grayscale images.
For the best results, don’t use the eyedroppers in images that require a large adjustment to map a pixel to the
maximum highlight or minimum shadow values.
Important: Using the eyedroppers undoes any previous adjustment you made in Levels or Curves. If you plan to use the
eyedroppers, it’s best to use them first and then fine-tune your adjustments with the Levels sliders or Curves points.
1 Identify a highlight, midtone, and shadow area that should be neutral gray. Depending on the image and the result
you want, you may need to identify only one area.
Use a color sampler to mark a neutral area so that you can click it with an eyedropper later.
2 Open the Levels or Curves dialog box. Choose Image > Adjustments, and then choose Levels or Curves. You can
also use an adjustment layer.
3 Double-click the Set Black Point tool , the Set Gray Point tool , or the Set White Point Eyedropper tool .
Use the Adobe Color Picker to specify a neutral target color.
If you’re working in RGB, enter the same values for R, G, and B to specify a neutral color. The neutral color should
be close as possible to the values of the color sampler.
If you want to preserve specific details in the shadow or highlight, specify a value for the Set Black Point and the Set
White Point Eyedropper tools that are within the gamut of the output device (printing press, laser printer, and so
forth).
4 With the targeted eyedropper, click the neutral area that you identified earlier. Make sure to use the appropriate
tool for the shadow and highlight.
5 Repeat steps 3 and 4 using a different eyedropper if necessary. Click on a selected eyedropper to deselect it.