We have 3 Hamsters (two dwarfs & a Syrian) and the drawfs get hand fed seeds at the bars, and lately this has caused them to nip my fingers, its because their eyesight isn't brilliant and they assume your fingers mean food. They are too quick to handle, but the Syrian hamster we handled from a young age so they were used to be handled. Some hamsters have red eyes, a white hamster we had, had red eyes. They will bite if scared.
You did well to get good pictures, they are normally too quick to photograph.