Fundamentals

The Exposure Triangle

Aperture, shutter speed, and ISO — how three controls make one exposure.

One exposure, three levers

Every photograph's brightness comes from exactly three settings working together: how wide the lens opens (aperture), how long the sensor is exposed (shutter speed), and how strongly the signal is amplified (ISO). Move any one and the exposure changes — but each also changes something else about the image.

The trade-offs

A wide aperture lets in more light but blurs the background. A slow shutter lets in more light but can blur motion. A high ISO brightens the image but adds grain. There's no free brightness — only trade-offs you choose on purpose.

Reading your intent

Before touching a dial, decide what the photo needs: frozen motion, a blurred background, or everything sharp. That intent tells you which setting to change first, and which side effect you're willing to accept.

Now practice it

Open the 2D Studio and try to correctly expose the scene for each of the four shooting intents.

Open the studio →

Practice challenges

Correctly expose a scene using only a wide aperture, then only a fast shutter. Try it →
Freeze a fast-moving subject without raising ISO above 400. Try it →
Deliberately overexpose a shot by two stops, then bring it back with one setting. Try it →

Prefer someone else behind the camera?

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