Single-lens reflex cameras, Image processing -- Digital techniques, CCD cameras -- Calibration, Charge coupled devices
Digital single-lens reflex (DSLR) cameras are examined and their dark current behavior is presented. We examine the influence of varying temperature, exposure time, and gain setting on dark current. Dark current behavior unique to sensors within such cameras is observed. In particular, heat is trapped within the camera body resulting in higher internal temperatures and an increase in dark current after successive images. We look at the possibility of correcting for the dark current, based on previous work done for scientific grade imagers, where hot pixels are used as indicators for the entire chip?s dark current behavior. Standard methods of dark current correction are compared to computed dark frames. Dark current is a concern for DSLR cameras as optimum conditions for limiting dark current, such as cooling the imager, are not easily obtained in the typical use of such imagers.
Justin C. Dunlap ; Oleg Sostin ; Ralf Widenhorn and Erik Bodegom, "Dark current behavior in DSLR cameras", Proc. SPIE 7249, Sensors, Cameras, and Systems for Industrial/Scientific Applications X, 72490N (January 27, 2009); http://dx.doi.org/10.1117/12.806128