Shutter Release button

Nikon D5100 shutter release button

Explanation: The shutter release button reacts in two steps:

  • Slightly pressing it until you feel the first resistance will activate autofocus and exposure metering
  • Pressing it further will actually take a picture.

The exposure metering will be continuously adjusted as long as you hold the button pressed – unless you have changed this in custom setting menu c1 shutter release button AE-L.

Recommendation: Use it frequently! But think beforehand 😉