# Exposure Calculator

Calculate equivalent camera exposures. Adjust aperture, shutter speed, or ISO and see the compensating settings to maintain the same exposure value.

## What this calculates

Dial in your camera settings with confidence. Enter your current aperture, shutter speed, and ISO, then pick a new aperture to see what shutter speed or ISO you need for the same exposure. Great for learning the exposure triangle or quickly adapting to changing light.

## Inputs

- **Aperture (f-stop)** — options: f/1.0, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32 — Lower f-numbers let in more light and create shallower depth of field
- **Shutter Speed** — options: 30s, 15s, 8s, 4s, 2s, 1s, 1/2s, 1/4s, 1/8s, 1/15s, 1/30s, 1/60s, 1/125s, 1/250s, 1/500s, 1/1000s, 1/2000s, 1/4000s, 1/8000s — How long the sensor is exposed to light
- **ISO** — options: ISO 50, ISO 100, ISO 200, ISO 400, ISO 800, ISO 1600, ISO 3200, ISO 6400, ISO 12800, ISO 25600 — Sensor sensitivity. Higher ISO = more noise
- **New Aperture (f-stop)** — options: f/1.0, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32 — Desired new aperture -- shutter speed and ISO will be adjusted

## Outputs

- **Exposure Value (EV)**
- **Sunny 16 Shutter Speed** — formatted as text — Shutter speed at f/16 using Sunny 16 rule
- **New Shutter Speed** — formatted as text
- **New ISO (same shutter)** — formatted as text
- **Aperture Change** — formatted as text

## Details

The exposure triangle connects three settings that control how much light reaches your camera sensor:

  - Aperture (f-stop) -- controls the size of the lens opening. Lower numbers = more light, shallower depth of field.

  - Shutter speed -- how long the sensor is exposed. Slower = more light, more motion blur.

  - ISO -- sensor sensitivity. Higher = brighter image but more noise/grain.

Exposure Value (EV) is calculated as: EV = log2(f^2 / t), where f is the f-number and t is the shutter speed in seconds.

The Sunny 16 Rule: On a bright sunny day, set your aperture to f/16 and your shutter speed to 1/ISO. For example, at ISO 200, use f/16 and 1/200s. This gives you a reliable starting point without a light meter.

Each full stop doubles or halves the light:

  - Aperture stops: f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22

  - Shutter stops: 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000

  - ISO stops: 100, 200, 400, 800, 1600, 3200

## Frequently Asked Questions

**Q: What is the exposure triangle?**

A: The exposure triangle is the relationship between aperture, shutter speed, and ISO. These three settings work together to determine the brightness of your photo. Changing one setting by one stop requires an equal and opposite change in another to maintain the same exposure.

**Q: How does the Sunny 16 rule work?**

A: On a clear sunny day, set your aperture to f/16 and your shutter speed to 1/ISO. At ISO 100, that means f/16 and 1/100s. For overcast conditions, open up to f/8. For heavy overcast or shade, try f/5.6. It is a quick way to get a usable exposure without a meter.

**Q: What aperture gives the sharpest results?**

A: Most lenses are sharpest 2-3 stops from wide open, typically around f/5.6 to f/11. Very small apertures like f/22 or f/32 cause diffraction, which actually softens the image. Use the smallest aperture you need for depth of field, but not smaller.

**Q: When should I raise ISO instead of opening the aperture?**

A: Raise ISO when you need a specific aperture for depth of field or a specific shutter speed to freeze motion. Modern cameras handle ISO 800-3200 very well. It is better to get a sharp, slightly noisy photo than a blurry, clean one.

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Source: https://vastcalc.com/calculators/everyday/photography-exposure
Category: Everyday Life
Last updated: 2026-04-08