Have you ever taken a photo that looked great on the back of your camera, only to realise later that it is slightly blurry? Camera shake is frustrating. Fortunately, there is a simple setting that can help you avoid it completely.
Auto ISO is an incredibly useful tool to have in your photography toolkit. It is especially handy if you prefer shooting in Aperture Priority (A) or Programme (P) modes. By switching this setting on, you allow your camera to raise the ISO automatically rather than dropping your shutter speed to achieve a correct exposure.
Here is exactly how it saves your shots.
The Classic Problem: Low Light and Slow Shutter Speeds
Imagine you are shooting in Aperture Priority mode. You want a deep depth of field, so you select a small aperture. If you have also manually locked your camera to a low ISO setting, your camera only has one way to let enough light in for a good exposure. It has to slow down the shutter speed.
If that shutter speed drops too low while you are holding the camera, your natural hand movements will cause camera shake, resulting in a blurry image.
The Solution: Let Auto ISO Do the Heavy Lifting
When you select Auto ISO, the camera gets much smarter about how it balances exposure. Instead of stubbornly lowering the shutter speed until your photo is guaranteed to be blurry, the camera will automatically raise the ISO instead.
Here is why Auto ISO is so helpful:
It prevents camera shake: By bumping up the ISO, the camera keeps your shutter speed fast enough to freeze your own hand movement.
It frees you up: You can focus entirely on your composition and choosing the right aperture for your creative vision, without constantly tweaking your ISO every time the light changes.
It adapts instantly: If you are moving from bright sunlight into a shadow, or if the sun dips behind a cloud, the camera adjusts the ISO immediately to keep your exposure perfect and your images sharp.
If you usually keep your ISO locked to a specific number, try switching it to Auto on your next photo walk. It is a brilliant, low-stress way to ensure your pictures come out sharp every single time.
Andrew Mason is a professional photographer and the founder of the 36exp Photographers School plus the London Photo Show.
He shoots mainly commercial portraits for a living, and likes to shoot landscape, portrait and travel photography.
He is a master of lighting and portrait photography, plus leads photography trips with 36exp.