Digital Camera Sensor Noise Estimation from Different Illuminations of Identical Subject Matter

A noise model that is generated from pictures taken by differently illuminating the same subject matter is presented. The superposigram, a three dimensional structure based on three different illuminations of the subject matter is used to directly calculate the noise present in the images which is attributable to the noise originating in the sensor array. Though a similar method has been used to determine the dynamic range compression present in a particular camera, this paper focuses on using data in which no dynamic range compression has taken place (raw files from a Nikon D2h were used). The paper shows through a mathematical proof that the noise in the camera is well estimated by the superposigram and then shows empirically that this is true. Finally, the method is applied to four commercially available cameras, to evaluate the noise in each