How to say "f-number" in Japanese

• 絞り値しぼりち
  nounCovers the f-number as the camera's aperture setting — the f-stop you choose for exposure; built on 絞り 'aperture', it is the wording that makes the link to the lens opening explicit.
• Ｆナンバーエフナンバー
  nounThe English term borrowed straight into katakana; it covers the f-number itself and is the choice when the English-style name is to be kept, as in technical description or translation.
• Ｆ値エフち
  nounA compact form, literally 'F value', covering the f-number and f-stop; it reads as technical notation, the kind of wording found in lens specifications where the value is stated numerically.
• 開放値かいほうち
  nounIts make-up, 開放 'opening', ties it to the aperture opened fully; although it does duty for f-number and f-stop, it is a marginal way to say 'f-number' and seldom the word you want.

For the f-number as the camera's aperture setting, 「絞り値」 is the wording that foregrounds the aperture; Ｆ値 is the compact technical form; 「Ｆナンバー」 simply transcribes the English; 開放値 is marginal and seldom needed.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 絞り値しぼりちf-number
• Ｆナンバーエフナンバーf-number
• Ｆ値エフちf-number
• 開放値かいほうちf-number