Sun and backlight compensation
CMOS sensor without auto iris, digital contrast enhancement and configurable exposure measurement zones guarantee optimal exposure control.
Most cameras with mechanical auto iris more or less shut down when they are confronted with backlight. Unfortunately, as a result, the darker areas become even darker and faces unrecognizable. Frequent attempts are made to brighten the image electronically using a backlight function, but the results are unsatisfactory since the auto-iris lens is closed.
MOBOTIX has taken a completely different approach to solving the problem. The CMOS sensors used in MOBOTIX cameras need no mechanical auto iris. Instead, they expose electronically from 1/8000th of a second to 1 second. This means that MOBOTIX cameras have no moving shutter parts that fail or freeze during winter. Without the auto iris, the camera can electronically choose what to see. To do so, exposure windows are easily configured and they inform the automatic exposure control which areas of the image to lighten up.
The exposure windows in the MOBOTIX camera can be freely configured in terms of number and position in the image; this can also be done remotely via the network. The example shows the differences between a shot without exposure windows and a shot using two exposure windows on both sides of the door.
When It Really Matters ...
The original scene at the bank shows just how important this feature is. In conventional cameras, the auto-iris lens would darken the faces in the foreground because of the brightness of the window. In the event of a hold-up, it would be very difficult to identify the criminal. By configuring the MOBOTIX camera with an exposure window in the lower half of the image, the light coming in through the window has no effect on exposure control. As a result, key areas of the image in front of the counter are illuminated to optimum effect.