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F-number

An f-number is a measure of the light-gathering ability of an optical system such as a camera lens. It is defined as the ratio of the system's focal length to the diameter of the entrance pupil ("clear aperture"). The f-number is also known as the focal ratio, f-ratio, or f-stop, and it is key in determining the depth of field, diffraction, and exposure…

History, Effect on exposure & Conventional scales

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Overview

Notation

Conventional scales

Effect on exposure

Effects on image sharpness

Human eye

Focal ratio in telescopes

History

Advanced semantic analysis

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Map overview Semantic statistics

F-number

Nodes89
Edges88
Triples90
Avg. degree1.98
Density0.022472
Components1

How this topic connects Entity context

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F-number

Top relations

related to T-stop · 12
F-number → Cinema, For, In, Lens, Minolta, Since, Smooth Trans Focus, Some, Sony, T-stop, T-stops, With
has effect · 10
F-number → As, At, Beyond, Depth, For, Rohr's, Tessar, The, Therefore, This
related to Fractional stops · 10
F-number → As, Click-stopped, EV, Half-stop, ISO, Most, On, Steps, The, Usually
related to Aperture numbering systems · 9
F-number → At, Bothamley, But, Eastman Kodak, For, Great Britain, Photographic Society, The, Uniform System
related to Conventional scales · 6
F-number → Each, EV, In, On, The, This
related to Gain · 5
F-number → In, Many, Most, T-stop, This
related to Human eye · 5
F-number → Computing, Some, The, Treating, Typically
related to Working f-number · 5
F-number → In, NA, Nw, The, This
related to Origins of relative aperture · 4
F-number → Dawson, In, John Henry Dallmeyer, Sutton
related to Sunny 16 rule · 4
F-number → An, ISO, Selecting, The

Important terminology Word statistics

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Important terminology

aperture lens exposure focal stop light diameter length system ratio used lenses pupil field image displaystyle one number focus photography

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
F-numberis ameasure of the light-gathering ability of an optical system such as a camera lens0.90text
a camera lensinstance ofAn f-number is a measure of the light-gathering ability of an optical system0.80text
Smooth Trans Focus lenses by Minoltainstance ofT-stops are still used in some kinds of special-purpose lenses0.80text
Sony.H-stopAn H-stopinstance ofT-stops are still used in some kinds of special-purpose lenses0.80text
Sonyinstance ofT-stops are still used in some kinds of special-purpose lenses0.80text
depth of fieldinstance ofand is used to control variables0.80text
F-numberhas effectDepth0.60section
F-numberhas effectThis0.60section
F-numberhas effectThe0.60section
F-numberhas effectRohr's0.60section
F-numberhas effectAs0.60section
F-numberhas effectTherefore0.60section

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