Photography Basics: Exposure Triangle Vocabulary

Vocabulary flashcards covering aperture, shutter speed, ISO, metering, histogram, stops, and related concepts from the lecture video.

Exposure Triangle

The balance of Aperture, Shutter Speed, and ISO used to achieve a properly exposed image.

Exposure Triangle

The balance of Aperture, Shutter Speed, and ISO used to achieve a properly exposed image.

Depth of Field

The portion of the image that is in sharp focus; larger opening yields shallower DOF, smaller opening yields deeper DOF.

f-stop

A value for aperture expressed as f/n; lower numbers mean larger openings and more light; higher numbers mean smaller openings.

Shutter Speed

The duration the camera sensor is exposed to light; longer speeds let in more light, shorter speeds let in less.

Stop (Exposure Stop)

A unit of exposure representing a doubling or halving of the light; one stop change doubles/halves exposure.

ISO

Sensor sensitivity to light; higher ISO brightens image but increases noise; doubling ISO increases exposure by one stop.

Noise

Digital grain/noise that appears at higher ISO, reducing image quality.

18% Grey (Middle Grey)

A standard mid-tone value used by cameras to estimate exposure; extreme tones can trick the meter.

Metering

How the camera measures light to set exposure; common modes include Matrix (Evaluative), Center-Weighted, and Spot (Canon also has Partial).

Matrix Metering (Evaluative Metering)

Multi-zone metering that analyzes the scene and averages exposure; good default for most subjects.

Center-Weighted Metering

Exposure reading weighted toward the center of the frame.

Spot Metering

Exposure reading from a very small area around the focus point for precise readings in high-contrast scenes.

Partial Metering

Canon variant similar to Spot Metering but covers a slightly larger central area (about 8%).

Histogram

A graph of the distribution of brightness values in an image; helps assess exposure and detect clipping; vertical axis shows pixel count.

Clipping

Loss of detail in shadows or highlights when tones are pushed beyond the sensor’s range; shown as edges on histogram.

Properly Exposed

An image that is neither too dark nor too bright, with visible detail in highlights and shadows.

Underexposed

Too little light recorded; image appears dark with lost detail in shadows.

Overexposed

Too much light recorded; highlights blown out with loss of detail.

Glass of Water Analogy

A visualization of exposure: ISO = glass size; aperture = rate of water flow; shutter speed = time the tap stays open.

P Mode (Program Mode)

Camera mode where the exposure is set automatically; you can still adjust settings with the main dial.

Aperture Stops

One-stop changes between neighboring f-numbers (e.g., f/4 to f/2.8); each stop changes light by about a factor of 2.

Shutter Speed Stops

One-stop changes in shutter time; doubling the duration increases exposure; halving decreases.

Motion and Shutter Speed

Fast shutter speeds freeze motion; slow speeds create motion blur or silky water effects.

Aperture and Depth of Field Relationship

Wider aperture (lower f-number) yields shallower DOF; smaller aperture (higher f-number) yields deeper DOF.