Dragging in a tilted image with the Straighten tool designates a reference in relation to which your photo will be rotated. What are the best references to look for?
What is the purpose of the grid overlays offered in the tool options pane when you select the Crop tool?
How do you use the different brushes and erasers that appear in the tool options pane when you select the Recompose tool?
How can you quickly undo a whole series of edit steps at once?
What are the similarities and differences between the Healing Brush tool and the Spot Healing Brush tool for retouching photos?