> I'd suggest a tool for photographic composition that has as options the
> rule of thirds or the golden ratio. So you can do photo composition on the
> fly and crop the image based on it.
Both the rectangle selection tool and the group tool support these "guides":
With this menu you can select the type of guides that is shown
within the selection to make the creation of a selection easier,
respecting Photo composition rules.
No guides are shown at all.
Only center lines are shown as guides within the selected area.
Rule of thirds
Guides are shown along the rule of thirds while creating the selection.
With this option, guides show up to mark the golden sections.
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