Curves adjustment

Settings

The following settings can be adjusted in the dialog:

• Select a colour mode (GREY/RGB/CMYK/LAB) from the first pop-up menu.
• Specify a single colour channel to apply the adjustment to, including the layer's alpha channel. Master (the default choice) applies the adjustment to all colour channels, excluding the alpha channel.
• Picker—click to activate the picker which allows you to drag on the image to modify the adjustment. Regardless of the colour model set, a click-drag places a node on the curve in relation to the selected pixel intensity; a 1x1 pixel area is considered. Secondly, dragging up (to lighten the image) or dragging down (to darken it) modifies the adjustment. The curve graph will update accordingly.
• X—accurately positions any added and currently selected node on the X-axis of the graph.
• Y—accurately positions any added and currently selected node on the Y-axis of the graph.
• Min and Max are the input minimums and input maximums and let you determine the range/threshold of values that are affected by the adjustment. It uses a normalised 0-1 range (regardless of bit depth) but setting Max to >1 allows the adjustment to manipulate HDR values as well. They can be also be used to fine-tune the manipulated tonal range in 8-bit and 16-bit documents.