Understanding Aperture on Your DSLR Camera
As you advance in photography and start learning more about the manual settings on your DSLR camera, aperture is one of the key concepts you’ll want to master. The aperture controls the amount of light that passes through the lens and hits the camera’s image sensor. Getting a handle on how aperture works is crucial for taking well-exposed photos and achieving the depth of field you want in your images.
What is Aperture?
The aperture is an opening in the lens that can be made wider or narrower. It contains small blades that work like the pupil in your eye, either dilating or contracting to control the flow of light. Aperture is measured in f-stops, with smaller f-stop numbers representing a wider opening that allows more light in. For example, f/2.8 is a very wide aperture that allows a lot of light, while f/22 is quite small and restricts light heavily.
Aperture and Depth of Field
In addition to controlling exposure, the aperture setting has a major impact on depth of field. Depth of field refers to the level of sharpness in the image, both in front of and behind the subject you focused on. A wider aperture like f/2.8 or f/4 produces a shallower depth of field, causing the background to appear beautifully blurred. This is great for portraiture when you want the subject to stand out against the soft backdrop.
On the other hand, a narrower aperture like f/16 or f/22 yields a deeper depth of field where more of the scene from foreground to background appears in sharp focus. This is ideal for landscape photography when you want to capture detail and clarity throughout the entire image.
Balancing Aperture with Shutter Speed and ISO
Aperture exists in a balancing act with the other two exposure settings, shutter speed and ISO. If you open up the aperture to allow in more light, you’ll need to increase the shutter speed and/or lower the ISO to avoid overexposure. Conversely, stopping down the aperture requires a slower shutter speed and/or higher ISO to compensate for the reduced light hitting the sensor.
When shooting handheld, you’ll generally want to use the widest aperture possible (lowest f-stop number) to allow for a faster shutter speed and prevent blur from camera shake. On a tripod, you can afford to stop down the aperture for deeper depth of field.
Mastering aperture and depth of field takes practice, but it’s a gateway to taking complete control over your photography and achieving the desired look for your imagery. So experiment with adjusting those f-stop settings and see the effects for yourself!
