The Exposure Triangle: Light, Time, and Depth
Move beyond automatic settings by mastering the interplay between aperture, shutter speed, and ISO to capture the exact mood and detail you envision.
Like Duolingo, but for The Exposure Triangle: Light, Time, and Depth. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
22 levels across 3 sections, about 44 minutes end to end, roughly 9 days at five minutes a day. It moves through Taking Manual Control, The Math of Light, and Creative Problem Solving. It assumes you already know the basics.
Free forever · No credit card · iPhone & Android
Key ideas in The Exposure Triangle: Light, Time, and Depth
- Aperture acts like a tap's width, controlling the volume of light flow
- Light meters aim for middle gray, often underexposing bright white scenes
- Shutter speed is the duration the tap stays open to fill the sensor bucket
- Intentional overexposure is needed to keep snow or bright skies looking white
- Total exposure is the volume of light collected during the sensor's active window
- The meter measures reflected light, which varies based on subject color
- Light as a finite resource and the 'bucket' analogy for exposure
- The internal light meter as a guide, not a dictator
- Reciprocity allows the same exposure via different setting combinations
- Widening the aperture by one stop requires doubling the shutter speed to stay equal
- Shutter speed priority is essential for freezing or blurring physical motion
- Aperture priority dictates the depth of field and background isolation
- Subject requirements determine which corner of the triangle is 'locked' first
- ISO is typically set first as a baseline for the environment's light level
- Reciprocity and maintaining the same brightness with different settings
- Aperture is chosen next to establish the creative 'look' of the focus
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives The Exposure Triangle: Light, Time, and Depth the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
If you want to increase the volume of light hitting your sensor without changing how long the shutter is open, what should you adjust?
Get it right to open this lesson and 21 more in the app.
How to learn The Exposure Triangle: Light, Time, and Depth, step by step
Go in order. 22 short levels across 3 sections, about 44 minutes in all, five minutes a day.
- 1
Taking Manual Control
- The Triangle in Action
- Aperture and the Plane of Focus
- Shutter Speed and Motion
- 2
The Math of Light
- Thinking in Stops
- ISO and the Digital Floor
- 3
Creative Problem Solving
- High-Contrast and Low-Light Mastery
- The Sensor's Perspective
3 sections · 7 units · 22 levels. Built to play, not to enroll.
Questions about The Exposure Triangle: Light, Time, and Depth
How do I learn The Exposure Triangle: Light, Time, and Depth?
Go in order: start with Taking Manual Control, then The Math of Light, then Creative Problem Solving. On Tomo that's 22 short levels, about 44 minutes in all, played five minutes a day. Start free and play the first level in under a minute.
Is there a Duolingo-style app for The Exposure Triangle: Light, Time, and Depth?
Yes. Tomo works like Duolingo: short daily lessons, streaks and quick quizzes. The Exposure Triangle: Light, Time, and Depth is one of its free courses, and you can type any other topic to get a course of your own.
Is The Exposure Triangle: Light, Time, and Depth free?
Yes. The Exposure Triangle: Light, Time, and Depth is playable on Tomo's free plan, which doesn't expire. No credit card, no waitlist. Download the app and start your first lesson.
How long does it take to learn The Exposure Triangle: Light, Time, and Depth?
22 levels across 3 sections, about 44 minutes of play in total. It's built for five minutes a day, so you finish it a little at a time instead of all at once.
Do I need any background to start The Exposure Triangle: Light, Time, and Depth?
No. It's pitched at an intermediate level, so it starts where you are and builds up. If you can tap a phone, you can start.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
The Exposure Triangle: Light, Time, and Depth is taught in the Professor style: clear, structured, thorough. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start The Exposure Triangle: Light, Time, and Depth today.
Download Tomo, search The Exposure Triangle: Light, Time, and Depth, and play your first lesson in under a minute.