Digital Photography Tips: Exposure, Shutter Speed And Aperture

Step 1: Shutter Speed

Your camera's shutter speed is basically the amount of time you're letting your camera look at things in the outside world. Shutter speeds come in various incremental steps, measured in seconds, ranging from 1 to 1/3000 or less.

So low shutter speeds are great for taking a snap of something fast-moving, because it's only looking at the fast-moving thing for a very short amount of time, and therefore can make a single image out of it without getting all confused.

A high shutter speed will give a great motion-blur effect, because the camera's looking at all the things that are going on for a long time, and amalgamating them into one, single image.

If you're using a high shutter speed, don't forget to take into account that your hands will probably be wobbling all over the place, so a sturdy tripod is well-advised.

Step 2: Aperture

The Aperture is the camera's eyes. Just like the human pupil, it goes small to take in less light, and big if it's dark to allow as much light in as possible. Flipping it off ‘automatic' allows you to control these settings, known as F-stops.

F-2 is a big hole, while F-16 is small, and each step along the way lets in precisely half as much light as the one before it.

A photo taken with a low F-Stop looks like this, while a photo with a high F-Stop will look like this.

Step 3: Reciprocity

It's at this point that we need to point out Reciprocity. This is the relationship between your shutter speed and the aperture – a small aperture with a long shutter speed is equivalent to a large aperture with a very short shutter speed.

Think of it like the amount of time it takes to fill a bucket from a tap. If the tap's only on a little bit, you'll need to leave it running for aaages, whereas if it's running full pelt the bucket will fill up sharpish. Apply that analogy to your camera, and it should all make perfect sense.

It's worth taking the time to fiddle about with Shutter Speeds and Aperture – if you know what you're doing you can take some amazingly unique and kooky photos, and remember – it's digital – so take lots and delete the ones that don't work.