An imaging system unit cell and method of detecting an image. One example of an imaging system unit cell includes a photodetector configured to generate a photo-current in response to receiving optical radiation, a variable capacitance charge storing circuit in electrical communication with the photodetector and configured to integrate an electrical charge accumulated from the photo-current, a control circuit configured to monitor an integration voltage across the variable capacitance charge storing circuit and adjust a capacitance of the variable capacitance charge storing circuit based on the integration voltage, and an output configured to provide an output voltage based at least in part on the integrated voltage.