Final answer:
Light adaptation is the process by which the eyes adjust to changes in lighting conditions. An example of light adaptation is when entering a dark movie theater after being outside in bright sunlight.
Step-by-step explanation:
The question asks which photo the instructor used to illustrate light adaptation. Unfortunately, without access to the specific course materials, I cannot provide the exact photo. However, I can explain what light adaptation is and provide an example.
Light adaptation is the process by which the eyes adjust to changes in lighting conditions. When moving from a dark environment to a bright one, the eyes need time to adjust, and vice versa. This allows us to see clearly despite varying levels of light.
For example, imagine entering a dark movie theater after being outside in bright sunlight. At first, everything appears dark, but after a few minutes, your eyes adjust and you can see the details in the theater. This is an example of light adaptation at work.