Selection of an image sensor
In Section 3.4.5 we discussed a simple linear noise model for imaging sensors, which proved worthwhile. You have two cameras at hand with the following noise characteristics:
Camera A = 1.0 + 0.1g
Camera B = 2.5 + 0.025g
Both cameras deliver digital signals with 12-bit resolution. Thus gray values g between 0 and 4095 can be measured. Both cameras have a quantum efficiency of 0.5. Which of the two cameras is better suited for the following tasks:
- Measurement of high gray values with the best possible relative resolution
- Measurement of the smallest possible irradiation. In order to decision correctly, compute the standard deviation at the highest digital gray value (g = 4095) and at the lowest value (dark image, g = 0). Further compute the number of photons that are equal to the standard deviation of the dark image.
