What is ISO sensitivity?
Learn about ISO sensitivity and how to optimize it for your next photoshoot.
ISO sensitivity, or ISO speed, measures how strongly your camera sensor responds to light. It’s basically your camera’s sensitivity to light. The higher the ISO sensitivity, the less light required to take a high-quality image. This is an important factor in determining your balance of settings in low or high light scenarios. Learn more about ISO sensitivity for your next photoshoot.
Learn the ISO basics.
Each time you double your ISO, your camera only needs half as much light. It’s an exponential effect that makes an exponential difference. Keep these effects in mind as you increase your ISO:
- Shutter speed: Shutter speed and ISO are directly tied. When your camera is more sensitive to light, it needs a quicker shutter speed to achieve the same clarity. For example, if you shoot with a shutter speed of 1/250 and a 200 ISO, changing to 400 ISO would give you the same exposure at a shutter speed of 1/500.
- Image noise: If you’ve ever seen that grainy look on old films, you’ve seen image noise. This blurred, “noisy” effect happens when your ISO is too high, making your camera too sensitive to light for the circumstance. It’s always best practice to default to the lowest ISO on your camera, to avoid over-sensitivity that can blur your image.
- High ISO: You might wonder when you'd even need to increase your ISO. Well, if you’re trying to get a clear photo of something in motion — say, a bird — you’d want to use a high ISO and a high shutter speed to freeze the image in place while keeping it high quality.
Edit your photos for even more clarity.
You can also heighten the light, minimize any noise, and clarify any blurriness in your editing process. Explore everything you can do with Adobe Photoshop Lightroom to edit stunning photos, all in one place.