Exposure Triangle
Compare aperture, shutter time, and ISO; explore equivalent exposures.
Positive brightness stops mean brighter than the reference; negative means darker. These are calculated relative settings, not a scene light meter.
Equivalent settings
Each row keeps reference ISO fixed: aperture × 2^(k/2), shutter × 2^k. Select a row to update the comparison only. Rows outside the shutter range are omitted.
| Aperture change (stops) | Aperture (f-number) | Shutter time (seconds) | ISO | Use settings |
|---|
A QUICK WALKTHROUGH
How to use this tool
- Enter reference and comparison settings.
- Calculate their ISO-adjusted exposure values.
- Select an equivalent row to compare it with the reference.
Formula and sign
EV = log2(N²/t) − log2(ISO/100). Brightness difference = reference EV − comparison EV. One positive stop corresponds to twice the modeled brightness.
Equivalent settings
Each row keeps reference ISO fixed: aperture × 2^(k/2), shutter × 2^k. Select a row to update the comparison only. Rows outside the shutter range are omitted.
Comparison settings
Settings are independent; no automatic locks. The model ignores lens transmission, sensor response, clipping, motion blur, and depth of field.
GOOD TO KNOW
Common questions
Does equivalent exposure mean the same photo?
No. Blur, depth of field and noise may differ; actual camera rendering is not modeled.