Panasonic Lumix DMC-FZ200 User Manual page 43

Shutter speed - this controls the amount of time that the light passing
through the lens diaphragm (or f-stop) reaches the sensor.
The amount of time multiplied by the light passing through the aperture
setting gives us the exposure.
When the aperture is set to a value which we want for a particular depth
of field then there will be an associated time value (or shutter speed)
required to achieve the correct exposure so that the image looks correct.
So for example if we have an aperture set on the camera at F4 and the
exposure system determines that a shutter speed of 1/60 second is
required to give the correct exposure, then if we adjust the aperture to a
smaller size (larger number) say f5.6, which is 1 f-stop increment smaller,
the camera will adjust the shutter speed to a longer value to allow the
same quantity of light (time x intensity) to reach the sensor.
In this case the shutter speed will go from 1/60 second to 1/30 second
i.e. the time doubles.
Here is the important relationship we must understand, increase the
intensity of light by opening the aperture (going to a smaller f-stop
number) means we need to make a corresponding decrease in shutter
speed to keep the exposure the same. Remember equal and opposite!
Shutter speeds are indicated as a fraction below 1 second, e.g. 1/25.
Speeds longer than 1 second are indicated 1" 2" 4" 8" etc.,
The fastest shutter speed of the FZ200 is 1/4000sec and the longest is
60 seconds in the manual, with manual focus mode.
1/125, 1/100, 1/80, 1/50, 1/40, 1/30, 1/25, 1/20, 1/15, 1/13, 1/10, 1/8, 1/6, 1/5
Faster slower
The higher the fractional number, the faster the shutter speed is
.
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