At its most basic level, photography is about two things: Light and Composition.
From your camera’s (technical) perspective, photography is all about one thing: Light.
There are three interrelated variables that allow you to determine how light is handled by your camera: Aperture, Shutter Speed, and ISO.
The art of photography is about balancing those three variables between the conditions you’re in and the style of photo you’re trying to capture.
The reason I say “balance” is that letting in more light always comes at cost.
Because each of these variables are connected (changing one affects the others), it’s important to know the “price” you’re paying when you decide to employ each method allowing light into the camera sensor.
The reason I say “art” is because there isn’t necessarily a “right” answer. It all comes down to the way you, the photographer, want to capture a scene or moment.
That said, here’s a quick breakdown of the three light variables and the “costs” for letting in more light with each:
- Wider Aperture = Less of the photo in focus
- Slower Shutter Speed = Moving objects appear blurry
- Higher ISO = More grain (noise)