f-number
noun
f-num·ber
ˈef-ˌnəm-bər 
1
: the ratio of the focal length to the aperture in an optical system
2
: a number following the symbol f/ that expresses the effectiveness of the aperture of a camera lens in relation to brightness of image so that the smaller the number the brighter the image and therefore the shorter the exposure required
Examples of f-number in a Sentence
Recent Examples on the Web
Use a low f-number (f/2.8 or f/4) to allow lots of light into your camera.
—
Jamie Carter, Forbes, 4 Oct. 2024
Jamie Carter, Forbes, 4 Oct. 2024
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'f-number.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Dictionary Entries Near f-number
Cite this Entry
“F-number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/f-number. Accessed 22 Oct. 2024.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share