Abstract: A chamber for a surveillance camera that is designed to be mounted inside a larger camera housing. The chamber is sealed and provides a controlled internal environment for sensitive camera optics and internal electronics. A flush mount window is provided for the front lens of the camera, and a sealed feed-through electronic connector is provided for attachment to external controls. Valves for both adding and removing gasses to/from the chamber are provided. In one embodiment, temperature, pressure and/or humidity sensors may be deployed inside the chamber and connected electronically to a display or computer for monitoring and adjustment. In another embodiment of, a heating element is provided to evaporate moisture from the camera lens and/or from the window, and to help control the temperature inside the chamber.