Depth of field

Definition
The zone in acceptable focus in front of and behind the focus point.
Advanced
Depth of field is affected by aperture, focal length, subject distance, and sensor size. Wider apertures and longer focal lengths reduce it; stopping down and stepping back increase it.
Why it matters
Directs viewer attention and determines how much of a scene is sharp.
Use cases
- Isolating a subject in portraits
- Ensuring full product sharpness for e-commerce
- Group photos where all faces must be in focus
Metrics
- Shallow: f/1.4 to f/2.8 at close distance
- Deep: f/8 to f/16 for products or landscapes
Issues
- Out-of-focus eyes in portraits
- Background distractions when the depth of field is too deep
Example
Shooting a three-person team portrait at f/4 and increasing distance to keep all faces sharp.