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
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Use a low f-number (f/2.8 or f/4) to allow lots of light into your camera.
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Jamie Carter, Forbes, 4 Oct. 2024
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Jamie Carter, Forbes, 4 Oct. 2024
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“F-number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/f-number. Accessed 2 Dec. 2024.
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