Exercise your ability to name and recognize feelings and emotions. Describe the feelings you see that the people in the pictures are feeling.
The important thing is to describe which feelings you see in the pictures, rather than whether or not they are correct. When you find yourself having judgements or reactions to the photos, it is a good idea to note those, but not let them deter from what you see.
Note that a person can feel several emotions at the same time. Those you recognize in a photo may change over time, depending on your own mood. Sometimes, the left and right eyes show a different feeling.
The reason for this exercise is actually not only to train your ability to name and recognize feelings. It also helps a lot to develop the mentality necessary to work through feelings. For that, it is needed that you don't act out feelings, and merely describing them does just that.
For developing these abilities, it is not necessary that you keep your descriptions. This is why they are not stored in any way here.