This week we are addressing aperture, the second of the three facets which make up the ‘triangle’ of photography. Aperture is a measurement of the amount the blades inside your lens open up to allow light to enter, and is measured in f stops. The wider an aperture, the more light is allowed in, and vice versa. This means that to compensate for a wider aperture (which will be measured by a low f stop, such as f1.8) a faster shutter speed is required to compensate and the same is true in reverse.
Aperture also controls the amount of area in focus, or the depth of field. A wider aperture, (e.g. 2.2) will give a shallow depth of field and a wider area that is out of focus in the foreground and background, otherwise known as bokeh. A smaller aperture (measured in larger numbers such as f22) will give you a much broader area of focus.
This week during the class exercise I was not feeling particularly inspired. I only had a prime lens with me having left my wide angle and telephoto lenses at home. On top of this it was pelting down with rain again and for whatever reason I was feeling unusually self conscious when going out to the city to shoot, so I let myself off the hook for once with the intent to complete the exercises later. Despite being last minute, I enjoyed the shoot I created today, and am myself partial to a wide aperture and a shallow depth of field.
Here is a link to an article with great explanations behind of the nitty gritty and mathematics behind aperture as well as other juicy details.