Image processing -- Digital techniques, Single-lens reflex cameras, Electric currents -- Measurement
A study of dark current in digital imagers within consumer grade digital cameras is presented. Dark current is shown to vary with temperature, exposure time, and ISO setting. Further, dark current is shown to increase in successive images during a series of images. Consumer cameras are often designed to be as compact as possible and therefore the digital imagers within the camera frame are prone to heat generated by nearby elements within the camera body. It is the scope of this work to characterize the dark current in such cameras and to show that the dark current, in part due to heat generated by the camera itself, can be corrected for by using hot pixels on the imager. This method generates computed dark frames based on the dark current indicator value of the hottest pixels on the chip. We compare this method to standard methods of dark current correction.
Justin C. Dunlap ; Erik Bodegom ; Ralf Widenhorn; Characterization and correction of dark current in compact consumer cameras. Proc. SPIE 7536, Sensors, Cameras, and Systems for Industrial/Scientific Applications XI, 75360J (January 25, 2010)