Why should I use WDR?
Wide dynamic range, or WDR, is an essential tool for getting clear, balanced videos without over- or underexposed sections. If your business has a large window, bright lights but dim hallways, or covered areas like parking garages that are extremely dark compared to the garage entrances and exits, WDR is something you should use.
What WDR does to help your videos remain clear even when you have dark and bright areas is to balance the lighting of both extremes into one consistent level throughout the image.
For example, a retail store may have a large window front that makes up a large portion of one wall; when someone walks in front of the window they will appear extremely dark compared to the window, and a standard camera may not record any recognizable features. With WDR, the lighting would be balanced so the window and person are both clear.
How does WDR work? WDR is actually made up of several features and factors. First, cameras with WDR have advanced light sensors that are more sensitive than standard surveillance cameras. This allows the camera to record better in a range of lighting, including low-light.
Second, the camera or its software will balance the lighting. This can actually happen in one of two ways. With tone mapping, the camera or the software will automatically brighten or darken areas. This is the standard method most surveillance cameras will use.
The other way is to record several versions of the exact same video at different exposure levels. Those overexposed and underexposed videos, along with the normal video, are then combined and the final video you see is the combined image. This type of WDR is only available on higher level professional cameras, however, because it requires an extremely fast light sensor.