Enhancing Images

Editing Curves Directly

Fine adjustments can be made to brightness and contrast in specific portions of the tone range by adding additional points to the curves for each channel. These points can be freely ad- justed by dragging them into new positions, changing the shape of the curve. Steepening the slope in a given portion of the curve will enhance contrast in that portion of the tone range. Changing the curve so that input levels in a given portion of the tone range are mapped to higher output levels will brighten tones in the affected tone range; similarly, changing the curve to map input levels to lower output levels will darken tones in the affected range.

Adding New Points to the Curve

Move the cursor over the curve edit display and click once to enter curve edit mode. Move the cursor to the position where you would like to add a new point, then click. A new point will be added at this position and the curve will automatically be adjusted to pass through this point. A point corresponding to a selected location in the active image can be added by click- ing the button and then clicking in the desired area in the image window. The position of the point can be adjusted by dragging it to a new location within the curve edit display. The image in the active window will automatically be adjusted to reflect changes to the curve.

Removing Points from the Curve

Points can be removed from the curve by dragging them out of the curve window.

Resetting the Active Curve to Linear

The default linear curve for the current channel can be restored by clicking the button in the Curves palette.

Resetting All Curves to Linear

To reset all curves to linear, click the button. All curves will be reset and the RGB master channel will be displayed in the Curve palette.

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Nikon 4 user manual Editing Curves Directly, Adding New Points to the Curve, Removing Points from the Curve