Aperture (F-Number)
0x829dAlso: FNumber, ApertureValue
How wide the lens opening was.
The f-number describes how wide the lens aperture was open. Confusingly, smaller numbers mean a wider opening: ƒ/1.8 lets in far more light (and blurs the background more) than ƒ/16.
EXIF stores it as a rational number. It controls both exposure and depth of field — the amount of the scene that is in focus.
Example value
ƒ/2.8
Typical range
ƒ/1.2 – ƒ/22
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