What isfocal length of lens

How to calculate focal length ofconvexlens

The camera works out the strength needed for the flash by metering the subject. You can also dial in more or less power with flash compensation. A lower power is often useful outside: it creates a fill light that subtly lifts shadows.

The shutter button triggers the camera’s shutter, which exposes the sensor to light that enters through the lens. A half-press of the shutter triggers the autofocus and locks the metering.