The definition of an aperture is a measure of how large an open lens (lens opening) is when we take a photo.
When we press the shutter button, the hole in front of our camera sensor will open, it’s the aperture setting that determines how big this hole is open.
The bigger the open hole, the more the amount of light that will enter is read by the sensor.
Aperture or openings are expressed in units of f-stop. Often we read the term openings / aperture 5.6, in more official photography languages can be expressed as f / 5.6.
As revealed above, the main function of the aperture is to control how large the hole in front of the sensor is.
The smaller the f-stop number means the bigger the hole is open (and the more volume of light entering) and vice versa, the greater the f-stop number the smaller the open hole.
AdiSo in fact, the aperture setting of f / 2.8 means a much larger opening than the f / 22 setting for example (you will often find the term fully open if you hear a photographer’s chat).
So the wide opening means the smaller the f number and the narrower the openings, the bigger the f number is.
••Understanding Depth of Field••
YangAnimation that shows sharp space that changes with changes in the lens aperture.
The depth of field – DOF, is a measure of how far the focus field is in a photo.
Wide depth of field (DOF) means that most of the object photos (from the closest object from the camera to the farthest object) will look sharp and focused.
While the narrow DOF (shallow) means that only parts of the object at certain points are sharp while the rest will be blurry / out of focus.
To get a wide DOF use a small aperture setting, for example f-22 (the smaller the aperture the wider the focal distance) – see the example photo above.
While to get a narrow DOF, use the aperture as big as possible, for example f / 2.8 – see the sample photo below.
This Depth of Field concept will be useful especially in portrait photography and macro photography, but actually all specialties will need it.