Camera Exposure Calculator

Photography isn’t just art it’s also science. If you've ever wondered how to balance your ISO, shutter speed, and aperture, you're not alone. That’s why we built the Camera Exposure Calculator a tool designed to take the guesswork out of perfect exposure.

What Is Camera Exposure?

Camera exposure is all about how much light hits your camera sensor. Too much light? Your photo looks washed out. Too little? It's too dark. Getting the right exposure means finding balance between three key settings:

• Aperture (f-stop) – Controls how wide your lens opens.
• Shutter Speed – Controls how long the lens stays open.
• ISO – Controls how sensitive the sensor is to light.

These three settings form what’s called the Exposure Triangle. Changing one means you often need to adjust the others. That’s where our calculator comes in.

How the Camera Exposure Calculator Works

Let’s keep it simple. You input:

• Aperture (e.g. f/5.6)
• Shutter Speed (e.g. 1/125s or 0.008 seconds)
• ISO (e.g. 100, 200, etc.)

The calculator then gives you:

• EV (Exposure Value) – A number that shows how much light you're letting in.
• EVₛ (ISO-adjusted EV) – Adjusted based on your ISO.
• Luminous Exposure – The actual light hitting the sensor, measured in lux·seconds.
• Equivalent Settings – Other combinations of aperture, ISO, and shutter that give the same exposure.

Camera Exposure Formula (No Math Degree Needed)

Here’s how we figure things out behind the scenes:

EV = log₂ (Aperture² / Shutter Speed)

EVₛ = EV + log₂ (ISO / 100)

Luminous Exposure = (0.65 × Luminance × Time) / Aperture²

We assume a standard lens transmission value (q = 0.65) for most lenses. If you don't know luminance, we estimate it using typical daylight (around 50,000 lux).

How to Use the Exposure Calculator

Step-by-step:

1. Enter your aperture, shutter speed, and ISO.
2. (Optional) Enter scene luminance if you know it.
3. Click calculate.
4. Instantly get your EV, ISO-adjusted EV, and luminous exposure.
5. Check the list of equivalent settings. These let you adjust your shot creatively without over- or under-exposing.

Real-Life Example:

You’re shooting a portrait on a sunny day.

You enter: f/4, 1/500s, ISO 100.

The calculator says EV = 14. That’s perfect for daylight.

Want more background blur? Try f/2.8, but it suggests adjusting your shutter to 1/1000s to keep the same exposure.

What Is a 10-Second Exposure?

That’s a long exposure. The shutter stays open for 10 full seconds. This lets in tons of light great for night shots, star trails, or smooth waterfalls. But be careful it can also cause blur if the camera moves even slightly. A tripod is your best friend here.

What Should My Camera Be On?

There’s no one-size-fits-all answer. It depends on:

• Lighting – Bright sun vs dim room
• Subject – Fast-moving action or still life?
• Creative Intent – Blurred motion or razor-sharp detail?

But with our calculator, you’ll know which combinations work for your shot.

Final Verdict

Photography doesn’t have to be a guessing game. Our Camera Exposure Calculator helps you make smarter choices every time you shoot. Whether you're just starting or already a pro, this tool saves time and makes your photos better.

So next time you're out shooting, don't second-guess your settings. Use our tool, and expose like a pro.

Frequently Asked Questions

How do you calculate exposure?

Use the formula:

EV = log₂ (aperture² / shutter speed)

Then adjust for ISO using:

EVₛ = EV + log₂ (ISO/100)

What’s a good exposure value?

EV 0 = f/1 at 1 second.

Bright daylight? Around EV 14–15.

Indoor? EV 6–9.

Night? EV 0–4.

Can I use this calculator for long exposures?

Yes! Enter your desired shutter time like 10 seconds and the tool will show if your other settings balance it.

Does ISO affect exposure?

Yes, it increases sensor sensitivity. Higher ISO = more brightness, but also more noise.

What's an "equivalent exposure"?

Different combinations of ISO, shutter, and aperture that give the same EV. For example:

• f/5.6 at 1/125s
• f/4 at 1/250s
  Both let in the same amount of light.