In the third of my blog articles on photography basics, we will look a bit more closely at aperture and aperture settings on a camera. If you remember in article one, when we discussed the modes, one of them were A or AV, which is Aperture Priority mode.
In short, aperture refers to the size of the opening in the lens when a picture is taken. The larger the hole, the more light will enter the hole and come into your lens and the smaller the hole, the less light will enter the hole and come into your lens.
With a wide aperture or large hole, less of your photograph will be in focus and with a narrow aperture or small hole; more of your photograph will be in focus.
Aperture is measure in fractions, and is indicated by an F, or fractional stops (f stops), thus an f/2.8 or f/5.6, which are larger fractions than f/8, f/11 or f/16, means that the hole is also larger. This also means that on f/2.8 or f/5.6 more of the photograph will be out of focus than on f/8, f/11 or f/16.
In practical terms, to remember the following is important:
A small f/# = a big hole in the lens = less in focus, because more light comes into the lens.
A big f/# = a small hole in the lens = more in focus, because less light comes into the lens.
How does this work for you in photography? If you want to blur the background in order to de-clutter the photograph and put more emphasis on your subject, you will need a small f/#, i.e. f/2.8 or f/5.6. This is desirable in most portraiture photography.
On the other hand, if you are photographing landscapes, you would want more of the photograph in focus and would thus use a larger f/ # such as f/8, f/11 or f/16.
Now on to your exercise:
If you do not have a camera where you can set the aperture, use the portrait and landscape settings on the dial and experiment to see how this change the photograph, looking especially at the background.
If you have a camera where you can set it to AV or A (Aperture priority mode), set it to AV or A.
Take two moveable objects and place them a short distance apart, i.e. 50 cm or 1 metre. Now start by setting your aperture on the smallest f/# available, i.e. f/2.8, f/4 or f.5.6. Focus on the closest subject and take a photo. Continue to do this by changing the f/# every time going from f/2.8 to f/4, f/5.6, f/6.3, f/8, f/11 up to f/16. Remember to focus on the exact same spot every time. Have a look at each photograph and see what you notice.
You are welcome to post your observations and photographs here once you have completed your exercise.
If you have any questions or comments regarding this article, please leave a comment below.
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