Understanding Aperture, ISO & Shutter Speed – The Exposure Triangle Explained

When you pick up a camera, three settings control how your image looks: Aperture, ISO, and Shutter Speed. Together, they make up what photographers call the Exposure Triangle and understanding them is the key to taking perfectly exposed, creative shots.

Here’s a simple breakdown:

Aperture – The Eye of the Lens

Aperture is like the pupil in your eye it can open wide or close down to let in more or less light.

Wide Aperture (small f-number like f/1.8) = More light, blurry background (great for portraits).

Narrow Aperture (large f-number like f/16) = Less light, more of the scene in focus (great for landscapes).

Why it’s important: Aperture doesn’t just affect brightness it also controls depth of field, which is how much of the image is in focus.

ISO – The Camera’s Sensitivity to Light

Think of ISO like your camera’s night vision.

Low ISO (100–400) = Best quality, less noise/grain, great for bright conditions.

High ISO (1600–6400+) = Brighter images in dark situations, but more grain/noise.

Why it’s important: ISO helps balance exposure when you can’t change aperture or shutter speed, but too much can make your images look rough and grainy.

Shutter Speed – Freezing or Blurring Motion

Shutter speed is how long your camera’s shutter stays open to let in light.

Fast Shutter (1/1000s) = Freezes action (sports, wildlife).

Slow Shutter (1/30s or longer) = Adds motion blur (light trails, silky waterfalls).

Why it’s important: It affects how movement appears in your shot — sharp and frozen, or soft and motion-filled.

The Exposure Triangle – Finding the Perfect Balance

These three settings are connected — change one, and you’ll probably need to adjust the others to keep the image correctly exposed.

More light from one setting means less is needed from the others.

It’s all about balance, depending on the mood, sharpness, and style you want.

Shooting in Manual Mode – A True Skill

In Manual Mode, you control all three settings yourself — instead of letting the camera decide. This takes skill because:

You have to think about both brightness and creative style.

Lighting changes constantly — and you need to adjust quickly.

You’re not relying on the camera’s auto mode to guess what you want — you’re in charge.

Why We Always Use Manual Mode for Video & Photography

At AJH Media, we shoot 100% in Manual Mode because:

Consistency – No sudden exposure changes in the middle of a shot.

Creative Control – We choose the exact depth of field, motion effect, and brightness we want.

Professional Quality – We can adapt instantly to different lighting conditions without losing image quality.

Cinematic Look – In video, controlling shutter speed and aperture is essential for smooth, natural-looking footage.

By mastering aperture, ISO, and shutter speed, we can create stunning, intentional images and videos — every single time.