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[7ravler]

What is a pre-event and post-event image? Does it take a picture before detection and after? Then theres Percentage and Sensitivity settings. What does the Percetage setting do? I don't understand the help file. The percentage goes up as motion is detected?

[JavaLawyer]

Correct, the pre/post- event settings capture images/video immediately before and after the triggered event.  The motion detection sensitivity percentage determines the degree of motion that will trigger an event.  A higher percentage will make the camera more sensitive to subtle changes, while as low percentage will require more dramatic motions in the camera field of view to trigger an event.

[7ravler]

Why don't they explain it like that in the manual?    Thanks.
Can I leave sensitivity to 0 and just go by percentage and visa versa?

[JavaLawyer]

Sensitivity settings (i.e. percentages) do not apply to PIR, which detects changing heat signatures in the camera field of view. Enabling and using Motion Detection (different from PIR)is impacted by the sensitivity settings. Contrary to PIR, motion detection uses an algorithm that detects pixel differences between successive video frames. Modifying the percentage will determine the degree of pixel changes that will trigger an event.

Here is an FAQ post relating to the DCS-9XX series cameras that will loosely apply to your camera as well.
DCS-9XX - Motion Detection Settings

[JavaLawyer]

I just drafted a Motion Detection FAQ entry to address other network camera owners with similar questions: DCS Network Cameras - Motion Detection vs. PIR

[7ravler]

Thank You.  D-Link should hire you for tech support! 

[JavaLawyer]

 

[7ravler]

Sorry to bother but... I'm still a little confused about Motion Detect setup. In the 2132L there are options for Sensitivity % and Percentage %.  Do I set a % for both settings?

[JavaLawyer]

Yes.

The Sensitivity setting determines how overt the motion must be to trigger an event (i.e. subtle vs. drastic). The Percentage setting determines what percentage of the camera frame must have motion activity to trigger an event. These two settings work in tandem to determine whether an event is triggered.

Examples.

• If the Sensitivity = 80% and Percentage = 1%, then a very subtle motion occurring in a 1% or greater area of the frame will trigger an event
  
• If the Sensitivity = 80% and Percentage = 90%, then a very subtle motion occurring that takes up 90% or greater of the camera frame will trigger an event.
  
  

Using these two scenarios, an oscillating fan on the far side of the room would trigger an event under scenario #1, but would not trigger an event under scenario #2, b/c the fan only takes up a tiny portion of the frame (e.g. 5%).

A person walking across the camera frame would trigger an event under both scenarios because the motion is occurring over close to 100% of the camera frame.

[JavaLawyer]

Adding to my last post, lets assume you only select 10 grid boxes in the frame for motion detection.

If the Percentage is set to 10%, then the motion only needs to occur in 1 grid box to trigger an event.
If the Percentage is set to 50%, then the motion must occur in at least 5 grid boxes to trigger an event.