Aperture

 

Aperture is the opening of a lens also known as F-Stop it is a very important part of the exposure triangle (ISO, Aperture, Shutter Speed). My lens the Sony FE 35mm f/1.4 has a range f/1.4 to f/16 which is amazing for low light scenes and capturing fast motion. Typically lenses are designed at f/2.8 or higher for more budget friendly prices. This is the exposure triangle it consists of the tree variables that adjust how a camera captures light: aperture, shutter speed, and ISO. Together, these three elements properly expose a shot. The three variables of the exposure triangle are all dependent on each other.

When the F-stop is wide open at f/1.4 the background is entirely out of focus while the subject is tack sharp. These wide open F-stop's are typically reserved for very low light situations when you really need to capture as much of the light you can without cranking the ISO function which produces more image noise. I will cover the ISO topic at a later date.

When the F-stop is narrow it reduces the amount of light entering the lens to the sensor. This also bring the rest of the background into focus.

One interesting effect that happens when the f-stop becomes smaller is lights begin to "burst" which can greatly improve an images quality if your shooting professional.

Typically on most dedicated camera systems you can set the mode to aperture priority where you manually set the aperture and the camera compensates the ISO/Shutter speed to acquire a quality image. A-mode is essentially set-it-and-forget it mode which most photos will be shot in. Other modes I have not covered are M-mode for manual settings where you have complete control of all three settings for a more personal touch because the software is only guessing at what your doing depending on what's in focus. S-mode is for changing shutter speed to capture high speed action.