We have a straight crack in the image below that we want to remove. The clone tool is a good choice to remove a line like this, but instead of going over the crack manually, let’s use a faster way.

Select the clone tool and make sure that the option Aligned is selected in the option bar and choose a size for our clone tool that’s slightly larger than the width of our crack. You can easily change the size of your brush by simply right clicking inside your document window (Control + click on the Mac). When you do this, make sure that you select a soft round brush (hardness = 0%)

Go to the top of the crack and mark the area beside it as the source of our clone tool by clicking on it while holding down the Alt key (Option key on the Mac) (A)

Position your mouse cursor at the top of the crack (B), hold down the shift key and click once, move the mouse cursor to the bottom of the crack (C) and click again and release the shift key.

So with a few clicks we were able to remove the complete crack. You might consider to clone a few extra random areas as a finishing touch (to avoid visibile patterns).

Note: retouching in a straight line also works with several other tools like the burn, dodge and sponge tool. Also remember that you can stroke a path with any of these tools.