LESSON 2
Exposure & the Pupil
Your eye already knows how to control exposure. Watch it happen.
Today's core idea: exposure is about how much light reaches the camera's sensor — and your own eye already does this automatically, every time your pupil opens or closes.
Your pupil is the opening light passes through to reach the back of your eye. In dim light it opens wider to let more light in. In bright light it shrinks to let less light in. This is exactly what a camera's aperture does — and it's the first form of exposure control you ever had.
Your body already reflects intentional design — this didn't happen by accident.
“I will praise you because I have been remarkably and wondrously made. Your works are wondrous, and I know this very well.”
Psalm 139:14, CSB
The same care that shaped how your pupil responds to light shaped everything else about you too.
Write in your own words: how is a pupil like a camera aperture?
Find a partner or a mirror. For each situation below, look closely at the pupil (yours or your partner's) and sketch how big it looks inside the circle. Don't worry about being exact — just capture roughly how open or closed it is.
Bright outdoor sun
midday, out in the open
Single lamp, indoors
one lamp on, in the corner of a room
Shade under a tree
looking out toward a bright, sunlit field
Dark room
lights off, minimal light
Pick one moment today to actually watch it happen: step from a dark room into bright light (or the reverse), and watch your pupil react in a mirror if you can.
Exposure isn't just physical — it's personal. People are drawn to different amounts of light. There's no right answer here, just notice your own preference.
Why do you think that is?
Does this match your pupil and light preference above, or is it different?
Send Your Answers
Photos and sketches stay saved right here on this device — we'll look at those together in class. This sends just your written answers to your instructor.