Definition |
Time the sensor is exposed to light |
Sensor’s sensitivity to light |
Size of the lens opening |
Measured In |
Seconds or fractions (e.g., 1/1000s, 5s) |
ISO numbers (e.g., ISO 100, 3200) |
F-stop numbers (e.g., f/1.8, f/16) |
Primary Effect |
Controls brightness via exposure time |
Affects image brightness and noise |
Controls brightness via light entry size |
Secondary Effects |
Affects motion blur (fast = freeze, slow = blur) |
High ISO increases noise, low ISO reduces noise |
Affects depth of field (wide = shallow, narrow = deep) |
Creative Uses |
Freeze action or create motion blur |
Shoot in low light, control noise |
Isolate subjects or keep scenes sharp |
Considerations |
Risk of camera shake at slow speeds |
High ISO can add noise |
Wide apertures require precise focus, narrow apertures can reduce sharpness |