A controller for an image sensor includes a mode selector that receives a selection between image capture mode and data capture mode. An exposure sensor collects exposure data for a scene falling on the image sensor. A command interface sends commands to the image sensor to cause the image sensor to capture an image with a rolling reset shutter operation in which an integration interval for the image sensor is set based on the exposure data if the image capture mode is selected. The integration interval for the image sensor is set to less than two row periods, preferably close to one row period, without regard to the exposure data if the data capture mode is selected. An analog gain may be increased to as large a value as possible in data capture mode. All pixels in a row may be summed before AD conversion in data capture mode.