One of the first things a photographer will want to understand is aperture and shutter speed. They work together in getting the right exposure, and allow photographers to get creative. If you want to grasp depth of field, motion blur or just want to experiment with your shots, you are going to have to become familiar with the different settings, symbols and how both aperture and shutter speed work together.

To begin with, aperture is the little opening in the lens. Sort of like the pupil of the eye, the size of that opening determines how much light passes through to the sensor or film. The most annoying thing about aperture is how it’s denoted. It’s counted in f stops, like f/2.8 or f/22, but the smaller the f stop number, the bigger the opening. Take a moment to bend your mind around that, when someone is talking about a higher aperture, they mean a smaller opening. From one f stop to the next means halving or doubling the amount of light that gets through.

The shutter is the curtain in front of the sensor or film, and how fast it opens and closes determines how much light comes in. Less time means less light which means darker, unless the aperture is made larger or the ISO sensitivity increased. Shutter speed is counted in seconds or more often in fractions of seconds all the way down to 1/1000 or more.

Generally for photography, the aperture and shutter speed work together to find that just right exposure. Think Goldilocks. Too little light means it's underexposed, too much light means it's overexposed and somewhere in the middle it's just right. You can raise the shutter speed and lower the aperture or vice versa and get about the same amount of light hitting the sensor. Different combinations may get you the same amount of light coming through, but it does tend to change the final outcome of the picture. That’s where photographers often get creative by trying different combinations.

By changing the aperture you often affect the depth of field (DOF), which in a picture is often shown by far away or close objects that are blurred. A low aperture will mean that distant objects are blurred while a high aperture means distant objects are in focus. Changing shutter speed can freeze a fast action like sports players, cars or any moving object. Slower shutter speeds can blur motion, making waterfalls a misty blur or traffic on a highway, whizzing lights.

To get creative with both aperture and shutter speed, photographers with DSLRs need to get familiar with the different modes. Most people are content to stay on auto, where the camera makes all the decisions about aperture, shutter speed, ISO and white balance. For the slightly more adventurous, there’s program mode, where the camera will decide the aperture and shutter speed for you, but not the ISO and white balance. To experiment with aperture and shutter speed, users will need to become familiar with the aperture priority mode (Av or A) and shutter priority mode (Tv or S). These allow you to change aperture while camera controls the shutter speed, or lets you change the shutter speed while the camera alters the aperture accordingly.

For the very keen minded experimenter, the manual mode (M) allows the photographer to change everything and lets the camera relax. It takes a lot of work to take pictures in manual, as you need to control not only aperture and shutter speed, trying to find the right combination to get the exposure right but also ISO and white balance. But manual can let you do some extreme things like make light sculptures.

Once photographers understand what aperture and shutter speed are, they have a whole new chapter of techniques to play around with, from Bokeh to depth of field or simply experimenting to freeze action or take photographs of the stars travelling across the sky.