Q:  What is S filter, how can S filter be beneficial to image quality?

A:  S filter is the nick name for MINTRON proprietary infrared filter, if installed in alpha series camera the white balance range will be extended and the color rendering will be much better especially using the camera under fluorescent lamp.

More:  Most of the color CCD cameras in the market are using dichroic filter to reduce the unwanted infra red so that infrared will not be misinterpreted as red color. A typical 33-layer coating will be able to provide a good cut of of infrared on 750nm, however, if using a CCD camera with this kind of inexpensive IR filter under illumination of tungsten lamp with color temperature of 3200k or lower, the steep-up of energy of red to infrared spectrum will not be able to stop properly and will cause bad white balance and color rendering. The customers using CCD camera Marjory under illumination of tungsten lamp are recommended to use S filter for the best result.