Pillars of Photography – Understanding Aperture for Beginners
Understanding Aperture for Beginners
Its one of the 3 basic pillars of photography, other two are ISO and Shutter Speed. Aperture is a opening or a hole which control the amount of light reaches to its sensor. It also controls the depth of field in your picture like whether you want a landscape shot where background and foreground both are super sharp or in other case you may want to shot a portrait where subject should be highlighted with blurred background or bokeh effect.
How Aperture control Exposure :
A bigger f stop means Bigger F number like f/8.0 or f/16.0 and smaller means like f/1.8 or f/1.4, but as the Aperture number increases the size of lens opening is decreases. f.1.8 (Bigger Opening/ More light ) > f/16 (Lesser opening/ less light)
You can see here too much light has blown out the image details. Its look like washed out. Its not soothing to eyes as well.
Underexposed image – Less light ( Bigger number like f/8.0 – f/10.0
Well Exposed Image :
Apertures are denoted by f number as below :
Note here, bigger f number means smaller hole (less light) and smaller f number means bigger lens opening (more light).
How Aperture Affects Depth of Field :
In generic term, we can call it as BOKEH effect or BLUR.
Depth of field is defined as “the zone of acceptable sharpness in front of and behind the subject on which the lens is focused.” or we can say, how sharp or blurry is the area behind your subject.
The shot on the left side clicked @50mm with f/2.0 aperture which results blur in background and foreground will be sharp, this is called as Bokeh effect normally used while clicking portrait. The one on right side is clicked with f/16, means foreground and background both will be super sharp. We normally use bigger f number to shot landscapes where we need everything super sharp, foreground plus background.
How Aperture Relates to Shutter Speed:
A low f/stop like f/1.4 or f/1.8 means more light is reaching to sensor and therefore the shutter doesn’t need to stay open as long to make a correct exposure, which means you need to have faster shutter speed. And vice versa, for bigger f/stop like f/8.0 or /16.0 less light reaches to sensor hence it will need slower shutter speed to get enough light to make perfectly exposed picture.
Some examples with Exif referring to above :
Some Pictures for your reference from my gallery :
Tips for Choosing Aperture:
Bigger Opening of lens = More light = Bokeh Effect (Blur background and sharp foreground)
Smaller opening of lens= Less light = Super sharp foreground as well as background.