[robertyip]

Why I use P-mode or Auto-mode with speedlite 430EX, the aperture is 4.0 and shutter speed is 1/60. When I use A-mode, I keep the aperture at 4.0 but the shutter speed drop to 1/8. Why the shuttter speed is not the same as when using same no of aperture, iso and flash? Who else can teach me how to enhance my technique?

[micros]

一般用 flash 都係有主體又有背景﹐其實要對背景用主體分開處理。
光圈用快門決定曝幾多現場光﹐閃燈負責主體。

canon o既 p mode lock 快門﹐係暗o既地方(如正常快門係 1/60以下時) 就會 under﹐背景黑而得主體有閃光。
a mode 就唔會 lock 快門﹐出o黎o既光圈快門係曝足現場光o既﹐咁個背景就正常。
設計就係如此。

有時用 m mode 仲好﹐可以自己決定曝幾多現場光控制背景。

[robertyip]

Thank you very much, hope you can teach me more later.