f-number

基本解釋

The matric characteristics and convergences on F-number space are investigated.
探討了F數(shù)空間的度量特征及幾種收斂性的關(guān)系。
When shooting, use a high F-number, this will help to blur the background and focus on the water.
拍攝過程中選用大光圈，這能模糊背景，從而關(guān)注水。
The aperture size (area of the aperture) of a lens could be calculated from focal length and the correspondent f-number.
光圈孔的大小，可從鏡頭的焦距與焦距比數(shù)中計(jì)算出來。

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An end-of-year report by Finnish software security company F-Secure highlights the growing number of hackers targeting Apple systems with malicious software, some of which could allow cybercriminals to steal security passwords.
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CENTERFORSECURITYPOLICY: Center for Security Policy

the numerical value of the relative aperture. If the relative aperture is f8, 8 is the f-number and indicates that the focal length of the lens is 8 times the size of the lens aperture &rarrsee alsoT-number