Viewing device

A UVB-visible hybrid system and method for visualizing a scene comprising one or more terrestrial corona discharge(s) and one or more objects is disclosed. A UVB image of the scene 200 is generated using UVB light which passes though a corona-peak tuned optical filter 410 configured to filter out sufficient non-terrestrial-corona light so that the generated UVB image is object-devoid. A visible-band imaging apparatus 500 comprises an array of photo-detectors 532 and is configured to generate a visible image of the scene. A derivative of the object-devoid UVB image is superposed with the visible-band image of the scene and displayed on a display device 580. The UVB imaging apparatus 400 and the visible-band imaging apparatus 500 share a common optical axis; the array of photo-detectors is disposed in the field of view of the UVB imaging apparatus. The object-devoid UVB image may be analyzed to classify pixels thereof as corona-discharge pixels or non-corona-discharge pixels. In some embodiments, the optical filter 410 has an average optical density over the [290 nm, 700 nm] spectrum of at least 4.