FrankLIN offers some automatic functions for correcting control curves. This can be a particular advantage if, say, an otherwise satisfactory set of control curves exists for a picture but it shows a colour-cast that is to be eliminated.
These functions depend on the current control curve type and hence are not always available:
Clicking on the Corrections
button opens a popup where
you can select one of the primary (R, G, B) or secondary (C, Y, M)
hues that is to be corrected. Selecting one of the entries opens a
numeric popup where you can input the desired value for the change.
Again the measurement unit changes between p
and %
according to the selection made in the Edit control points
dialog. Positive values increase and negative values decrease the
amount of the respective colour.
After inputting a positive value as above, the control curves are altered so that the lighter parts are increased and darker parts decreased. This ensures that during later reproduction of an image very light areas do not bleach out and very dark ones do not block up.
This allows monochrome images (*.IMG etc.) that have a
small
CK3 control curve to be coloured. This CK3 control curve
looks completely different from the usual diagonal control curves and
you can see at once that you can only set two colour values, namely
for the foreground and background. In this way monochrome images are
more correctly duochrome images, even when they are only in black and
white.
After selecting in the subdialog whether Foreground or Background is to be coloured, you can select the desired colour conveniently from the Calamus Colour-circle dialog box. You can use palette colours as well as spot colours. The conversion to the correct RGB values (spot colour layer is not retained!) is undertaken by FrankLIN.
The intensity
of the foreground and/or background colours
and the difference
between them can also be altered with the
Contrast and Brightness sliders, or by clicking the mouse in the
relevant half of the control curve graph. You can even swap foreground
and background colours in this way. (This trick also works with
duochrome graphics that have not been coloured!)
