147C.Fn-03 is unused.3Custom Function SettingsC.Fn-01 Viewfinder display during exposure1: Displays the exposure information and number of remaining shotsduring continuous shooting.C.Fn-02 Shutter release without card1: The shutter button will not work without a memory card in thecamera. This prevents shooting without a memory card.If there is no memory card and you press the shutter button,“Card” will blink on the top LCD panel and in the viewfinder. Itindicates that C.Fn-02-1 is in effect.C.Fn-04 Shutter button/AE lock button1: You can focus at one location and obtain AE lock at anotherlocation in the scene. Press the <w> button to autofocus andpress the shutter button halfway to attain AE lock.2: In the AI Servo AF mode, you can press the <w> button to stopthe AF operation momentarily. This prevents the AF from beingthrown off by any obstacle passing between the camera andsubject. The exposure is set at the moment the picture is taken.3: This is useful for subjects which keep moving and stoppingrepeatedly. In the AI Servo AF mode, you can press the <w>button to start or stop the AI Servo AF operation. The exposure isset at the moment the picture is taken. Thus, the focusing andexposure will always be at the optimum point as you wait for thedecisive moment.C.Fn-04 and C.Fn-19-0/1/2 (p.153) both have AF start/stop and AElock functions. If you have set both these Custom Functions and youexecute both Custom Function operations, the latter operation will notwork. The only exception will be when AF stop is executed after AFstart.
