Adjusting the Tone Curve

Use the tone curve to fine-tune the tone and color of the image. The tone curve consists of a horizontal axis (input value, before adjustment) and a vertical axis (output value, after adjustment).

The horizontal axis indicates the original brightness of the image. The vertical axis expresses the brightness after adjustment. The left edge of the horizontal axis indicates white (the brightest part). The right edge of this axis indicates black (the darkest part). The top edge of the vertical axis indicates black (the darkest part). The bottom edge of this axis indicates white (the brightest part).
tonecurbgraph

Generally, you only need to make minor adjustments to the tone curve when adjusting the tone and colors of an image. Note that adjustments to the image tone and color by way of the tone curve work in addition to the adjustments made with Level Adjustment and enable more subtle adjustments.

Procedure
  1. Perform the operation shown below according to what is being set.
    • Job: Double-click the job to open the Job Settings window.
    • Queue folder: Click for the queue folder to open the Queue Properties window.
  2. Click .
  3. Click Edit Tone Curves.
    The Tone Curves window appears.
  4. Under Channel, select the color whose tone will be fine-tuned.
    You can adjust all colors at the same time by selecting Apply to All Colors.
  5. Edit the tone curve.
    1. Click a certain point on the tone curve (the black line).
      A black dot (a control point) appears at the point you clicked. You can add multiple control points.
    2. Use one of the following methods to adjust the shape of the tone curve by moving the control point:
    • Drag the control point:

      Point to the control point, and then drag it when the pointer's shape changes to .

    • Click the control point, and then enter the value in IN or OUT:

      The adjusted result is applied immediately to the layout area preview display.

    IMPORTANT
    • If you have already adjusted the levels with Level Adjustment, selecting the Show All Channels check box displays under Tone Curves the curves of the colors that have undergone Level Adjustment.
      tonecurb
    • When there are multiple control points, control points other than the one being dragged are fixed in place. This makes it possible to select and adjust just a specific tone area.
    • To initialize the tone curve, click Reset.
  6. Click OK.
    The Tone Curves window closes.
  7. Click OK.