BLC stands for BackLight Compensation. The problem of over-exposure plagues all but the most expensive cameras on the market and is usually dealt with in a range of products known as the WDR (Wide Dynamic Range). Some of our high end cameras use various techniques to control light, but no-one has yet to master all eventualities.

The diagram opposite shows a very unique feature that compensates using a rectangle that is both sizable and movable within the image handling over exposure. In this demonstration flood lighting is hitting the side of the van causing the side door panel and side rear panel of the vehicle to have a mild white out effect. By switching on the BLC function to "User Configure", the rectangle appears on the image. By selecting "Size" the rectangle can be increased or decreased in size and by selecting "Location" the rectangle can be moved around the image area. When placed over an area of over-exposure, the camera is instructed to normalise this area, thus toning down the white-out effect and displaying a more accurate picture of the vehicle. VDT has tested this function and has found it to be a very useful feature and unique.