Response curves represent the noise intensity for each colour channel. Modify the red, green, or blue response curves to fine-tune the degrain. You can add vertices to a curve to refine your adjustments.
To modify the red, green, or blue curve:
- To display the response curve, click Show Curves.
- Show the response curve you want to modify by clicking the button corresponding to the colour of the curve.
The selected curve is highlighted.
- Sample the colour you want to use as a reference for your adjustments.
Red, green, and blue vertical lines representing the colour channels are plotted on the curve.
- Do one of the following:
- To add a vertex to the curve, place the mouse cursor over the area on the curve where you want to add the vertex and press A.
- To lock the curve in place while adding a vertex, press Shift+A on the curve.
- Click a vertex to display its tangent handle and then drag the handle to adjust the curve. You can also adjust the curve by dragging the vertex.
- Modify the curve until you are satisfied with the results:
- To select a vertex, click it. To select several vertices, draw a selection box around them.
- To move one or several selected vertices, drag a selected vertex. To restrict vertex movement to the Y axis, press Shift while moving the mouse. To restrict vertex movement to the X axis, press Shift+Alt while moving the mouse.
- To delete vertices, select them and then press D.