These are Lighting Effects from angles and the contrast of the light that is hitting an object or being. If it was hitting an object it would reflect light in a mirror, for example, we all know that mirrors can reflect the light to a different place and it can generate heat from the sun.

​

For an image of a picture, the light needs to reflect from an angle so I would try to enhance the color & light to make better quality.  

There are pictures on here as an example of light and contrast of the quality of the pictures. There are 5 photos that I've taken and adjusted the lighting and contrast to make the photo more realistic or non-realistic.