Commissioning of camera calibration factor for luminance measurement

Use of HDR (High Dynamic Range) images for critical luminance studies is an established fact now. Luminance measurement has to be done using a camera which is calibrated. The calibration factor, relating the luminance measured from the HDR images and luminance measured using a device, say a luminance meter, can be calculated using several methods. At the outset of launching new direction for general lighting practice using digital camera and also with the increased importance of lighting controls in interior and street lighting applications, there is a need to derive simplified algorithms for luminance and illuminance measurements using camera. Many researchers all over the globe are working in this direction, however, this paper describes a simplified approach for obtaining the calibration factor.