Learn how to greatly improve every portrait in which the subject is smiling by applying a little digital tooth whitening. In this easy to follow tutorial you will be whitening teeth in minutes. We will first select the teeth and soften the selection, to avoid a visible line between the areas that are lightened and the rest of the image. Although there are many ways to make a selection in Photoshop, using the Quick Selection Quick Mask works well when making a detailed selection such as selecting a person’s teeth.