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Adjust color and tonality with Curves



You can adjust the tonality and color of an image by changing the shape of the curve in the Curves adjustment. Moving the curve upward or downward lightens or darkens the image, depending on whether the dialog box is set to display levels or percentages. The steeper sections of the curve represent areas of higher contrast; flatter sections represent areas of lower contrast.

If the Curves adjustment is set to display levels rather than percentages, the highlights are represented in the upper-right corner of the graph. Moving a point in the top portion of the curve adjusts the highlights. Moving a point in the center of the curve adjusts the midtones, and moving a point in the bottom section of the curve adjusts the shadows. To darken highlights, move a point near the top of the curve downward. Moving a point either down or to the right maps the Input value to a lower Output value, and the image darkens. To lighten the shadows, move a point near the bottom of the curve upward. Moving a point either up or to the left maps a lower Input value to a higher Output value, and the image lightens.

Note: In general, only small curve adjustments are necessary to make tonal and color corrections to most images.
  1. Do one of the following:

    • Click the Curves icon  or a Curves preset in the Adjustments panel.

    • Choose Layer > New Adjustment Layer > Curves. Click OK in the New Layer dialog box.

    Note: You can also choose Image > Adjustments > Curves. But keep in mind that this method makes direct adjustments to the image layer and discards image information.
  2. (Optional) To adjust the color balance of the image, choose the channel or channels that you want to adjust from the Channel menu.
  3. (Optional) To edit a combination of color channels at the same time, Shift-click the channels in the Channels panel before choosing Curves. The Channel menu then displays the abbreviations for the target channels—for example, CM for cyan and magenta. It also contains the individual channels for the selected combination. This method does not work in a Curves adjustment layer.
    Note: select Channel Overlays in Curve Display Options to see the color channel curves superimposed on the composite curve.
  4. Add a point along the curve by doing one of the following:

    • Click directly on the curve.

    • Select the On-image adjustment tool , then click the area in the image that you want to adjust. Drag the pointer up or down to lighten or darken the values for all similar tones in the photo.

    To identify areas in the image that are being clipped (black or white), select Show Clipping in the Curves dialog box or Show Clipping For Black/White Points from the Adjustments panel menu.

    You can add up to 14 control points to the curve. To remove a control point, drag it off the graph, select it and press Delete, or Ctrl-click (Windows) or command-click (Mac OS) it. You cannot delete the endpoints of the curve.

    With the On-image adjustment tool selected, click three areas of an image to add points to the curve. Increased image contrast resulting from lightening the highlights and darkening displayed by an S-curve.

    To determine the lightest and darkest areas in an RGB image, drag across the image with the On-image adjustment tool. The Curves dialog box displays the intensity values of the area under the pointer, and the corresponding location on the curve. Dragging the pointer across a CMYK image shows the percentages in the Color panel, if it’s set to display CMYK values.
  5. Do one of the following to adjust the shape of the curve:

    • Click a point, and drag the curve until the tone and color look correct. Shift-click to select multiple points and move them at once.

    • Select the On-image adjustment tool . As you move the mouse pointer over the image it changes to an eyedropper, and an indicator on the curve shows the tonal value of the underlying pixels. Click on the image at the desired tonal value and drag vertically up or down to adjust the curve.

    • Click a point on the curve, and enter values in the Input and Output text boxes.

    • Select the pencil at the left of the curve grid, and drag to draw a new curve. You can hold down Shift to constrain the curve to a straight line, and click to define endpoints. When you are finished, click the Smooth icon  to smooth the curve (in the Curves Adjustments panel) or click Smooth (in the Curves dialog box).

    Points on the curve remain anchored until you move them. As a result, you can make an adjustment in one tonal area while other areas remain unaffected.

Apply an Auto correction

 Click Auto in the Curves Adjustments panel or in the Curves dialog box.

Auto applies an automatic color correction using the current default setting. To change the default setting, use options in the Auto Color Correction Options dialog box. You can apply an Auto Color, Auto Contrast, or Auto Tone correction to an image. For more information on these options, see Set Auto adjustment options.

Set black and white points using the black point and white point sliders

Use the Black and White sliders to quickly set black and white points. For example, if you move the black point slider to the right at input 5, Photoshop maps all the pixels at input 5 and lower to level 0. Similarly, if you move the white point slider to the left at level 243, Photoshop maps all pixels at level 243 and higher to level 255. The mapping affects the darkest and lightest pixels in each channel. The corresponding pixels in the other channels are adjusted proportionately to avoid altering the color balance.

  1. Drag the black and white point sliders to any point along the axis. As you drag, note that the input value changes.
  2. To preview clipping as you adjust black and white points, do one of the following:

    • Hold down Alt (Windows) or Option (Mac OS) as you drag the sliders.

    • Choose Show Clipping For Black/White Points from the Adjustments panel menu, or Show Clipping in the Curves dialog box.

Set black and white points using the eyedropper tools

  1. Double-click the Set Black Point Eyedropper tool. In the Adobe Color Picker, select a value where R, G, and B values are identical. To set the value to black, set R, G, and B values to 0.
  2. With the eyedropper, click on an area in the image that represents the black point, or the area with lowest tonal values.
  3. Double-click the Set White Point Eyedropper tool and select a color with identical R, G, and B values.
  4. Click in an image area with the lightest tonal values to set the white point.

Keyboard shortcuts: Curves adjustment

You can use these keyboard shortcuts in the Curves adjustment:

  • To set a point on the curve in the current channel specified in the Curves adjustment, 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.