Darktable is excellent at finding out what’s worth processing and what’s not worth processing. Darktable gives you the tools.
One of these tool is the Focus Peaking Mode. It works in both the Lighttable and the Darkroom.
Pressing “Ctrl-Shift-F” will enable the focus peaking mode.
The Focus Peaking mode uses a “heat map”
Focus Peaking in the Lighttable
Focus Peaking in the Darkroom
The yellow, green and blue colours are:
- Yellow: a very sharp edge.
- Green: a sharp edge.
- Blue: an “almost” sharp edge.
The terminology is a little bit murky. The Focus peaking mode shows the edges and analyses the edges which is different from the focus.
A surface without edge can be in focus, like the eyes of the dog in image #1. Since the eyes are black, there is no edge. It doesn’t show in the yellow, green or blue.
The eyes in image #3, the eyes are black and brown. They have an edge. They show the edge in the focus peaking mode.