User`s manual

Reference: The Advanced Image Correction tools 101
Use the Curve Pointer tool to define
points in the curve that will be
modified. When you click on any point
in the curve, a black handle appears
to mark your position. To remove the
handle, drag it off the graph.
Use the Curve Zoom Frame tool to
zoom in and out on a particular point in
the curve. Once the area is zoomed in,
you can then use the Curve Pointer
tool to define new points for better
precision. This is particularly useful for
working with 12-bit images, as more
detail can be seen in such images. The
zoom level can be seen in the Zoom
field. To zoom out, use Option-click
Use the Curve Move tool
to scroll through the curve
if the curve has been
zoomed in. This curve tool
can be used only if the
curve has been zoomed in
with the Curve Zoom
Frame button (left).
Otherwise, the Curve
Panel tool will be dimmed
Instead of dragging the
Gamma handle, you can
also directly enter the
appropriate Gamma value
in the edit box. Dragging
points on the curve to a
Gamma value above 1.00,
will lighten the dark tones.
Dragging points on the
curve to a Gamma value
below 1.00 will darken the
light tones
Appearance of curve if Method chosen is "Gamma"
Appearance of curve if Method chosen is "Line"