Now and then a lovely picture is spoiled by one small thing. A crisp packet by the path, a wire cutting across the sky, a spot of dust on the lens, a bin at the edge of a family portrait. Most editing tools have a touch-up feature that lets you brush over such details, and the picture fills in the gap using the area around it. Used with care, it can rescue a photograph you would otherwise have discarded.
Work slowly and zoom in
Open the picture and zoom in on the spot you want to change. Select the touch-up tool and set the brush to a size just a little larger than the object. Tap or draw gently over it and see what happens. Often the object simply disappears. If the result looks smudged, undo it and try again with a smaller brush, or start from a slightly different point. Patience is the secret of this tool.
The tool works best on simple backgrounds, such as sky, grass, water or a plain wall. On busy patterns like brickwork, railings or crowds it can produce odd repeating shapes. If that happens, try several small touches rather than one large one, and check each result before moving on. Sometimes it is easier to crop the picture slightly, so the distraction falls outside the frame, than to remove it.
Zoom out regularly to look at the whole picture at normal size. What looks perfect when magnified can appear strange from a distance, and what looks messy up close may be invisible at normal size. Compare with the original from time to time. A good repair is one that nobody notices, and if you have to search for it, you have probably done it well.
Be honest about what you change. Removing litter from a beautiful view is fine, but altering a picture so it gives a false idea of what happened is not. Never remove people from a group picture without their knowledge, and do not change a scene that you plan to present as a record of something. Keep the original, so the true version is always safe, and let the touch-up tool do only small, gentle work.