Knowledge base
article · CCTV
WDR explained: handling backlight in video surveillance
True WDR vs digital WDR, and how to place cameras facing windows and entrances.
Select Security1 min read
The problem
When a camera faces a bright window or entrance, the frame contains both very bright and dark areas, and faces turn into dark silhouettes.
Types of WDR
- True WDR: the sensor captures multiple exposures and merges them. Usually specified in decibels (e.g. 120 dB).
- Digital WDR (DWDR): software processing with weaker results under strong backlight.
Practical tips
- Where possible, mount the camera to the side of the light source rather than directly facing it.
- Choose True WDR models for entrances.
- Tune WDR/BLC/HLC on site and check at different times of day.
Check the WDR rating of a specific model in its datasheet.
#CCTV#WDR
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