[GapGapMan]

我想問長焦距同埋大光圈, 兩個出黎既淺景深有咩唔同??
幾時應該用前者, 幾時用後者?

[Excalibur0991]

你既問題本身有問題, 好難答.

景深既深淺係取決於光圈既實際大小.

光圈直徑= 鏡頭焦距/光圈值(f-number)

用呢條式就可以大概算出唔同條件既景深邊個深d, 邊個淺d

[dinalka]

Long focal length will decrease depth-of-view, and increase compression. For example 200mm to 400mm.

Large aperature just decrease depth-of-view, just blur the background.