关于我们 新闻与活动

宽动态范围

A scene with a very bright areas and a dark areas, or a backlight where there is a person at a bright entrance, takes the image in the dark areas almost invisible.
Panasonic security/surveillance cameras have processing functions that can display objects in both bright areas and dark areas to solve this problem.

What's Dynamic Range ?

The dynamic range of the security / surveillance camera means the range of the brightest and darkest areas that the image sensor can take image.
The range of the areas show the illuminance range, and the ratio of this brightness is expressed in decibel [unit:dB].

The table on the right shows the relation between illuminance ratio and dB.

Reference : dB = 20 log ( Brightest [lx] / Darkest [lx] )

Illminance and Dynamic Range

The illuminance of the object is a very important environmental factor.
Lux [lx] is used as an index representing this illuminance.
This indicates the amount of light per unit of time.
As a guide, the moonlight of the full moon is about 0.2 lux.
The figure below shows the relation between illuminance and dynamic range.
The dynamic range of the human eyes are about 100 dB, but the dynamic range of the image sensor is about 70 dB. Therefore, when trying to see a dark part like the image of "A", the bright part is not see.
Also, if trying to see the bright part like the image of "B", the dark part can not be seen.

In such a wide range-contrast environment, it is possible to generate an image with appropriate brightness by combining a dark image and a bright image. (WDR Function)
The security / surveillance camera with a WDR function like the image of "C" can record clear images in bright and dark areas by combining bright and dark areas.

144dB Super Wide Dynamic Range(Super WDR)

It is difficult to monitor the backlight environment.
In a room with large windows, the face of the person in the room looks dark for the backlight.
Although raising the brightness makes the face visible, there is a disadvantage that the background image blown out highlights.
Panasonic's Super WDR synthesizes images at different shutter speeds, You can see both brigth areas and dark areas.
Shoot brightly in dark places with a slow shutter speed and shoot so that it does not blown out highlights in bright places with fast shutter speed.
By combining these different shutter speed images, a wide dynamic range is realized.
The Panasonic EXTEME series security / surveillance cameras achieve 144 dB, which is over 133 dB of the conventional.
Conventional
Super WDR
For example, if the camera is pointed towards the entrance of a building, the camera will automatically detect faces and brighten this portion of the image.Combined with the new 144dB enhanced Super WDR capabilities, this high-performance face detection technology can clearly and automatically identify an individual’s face. It offers optimal facial recognition and can capture evidence even in dynamic scenes or heavily backlit conditions.
backtohome

Panasonic Security Cameras offers a large line-up, from analog cameras to IP cameras that are suitable for your purpose.