: Specify how long before the current frame the shutter should be opened.<br>
The unit is in frames. The higher the value, the bigger the blur.</LI>
<LI><b>Start Value</b> : Specify the strength of the blur when the shutter is opened.</LI>
<LI><b>Start Curve</b> : Specify how to apply the blur, from the time the shutter is opened up to<br>
the current frame. The default value is 1, with it the blur changes linearly.</LI>
<LI><b>Shutter End</b> : Specify how long after the current frame the shutter should be