The ability of Photoshop to recognize the people`s faces is limited just to portraits, where the model is looking in the camera (profile photos are still ignored). If Photoshop is not able to recognize a face correctly, then the picture editor has no choice but to use the following tools. Adobe provides a tool that is able to fix particular photos, but it has two significant disadvantages.
Fist of all, Photoshop does not pay any special attention to the possible surface structure features, like film grain, or scan traces, or faded color. This is, for example, the case with Leonardo da Vinci`s Mona Lisa.