An electron energy loss spectrometer is described having a direct detection sensor, a high speed shutter and a sensor processor wherein the sensor processor combines images from individual sensor read-outs and converts a two dimensional image from said sensor into a one dimensional spectrum and wherein the one dimensional spectrum is output to a computer and operation of the high speed shutter is integrated with timing of imaging the sensor. The shutter is controlled to allow reduction in exposure of images corresponding to the individual sensor readouts. A plurality of images are exposed by imaging less than the full possible exposure and wherein the plurality of images are combined to form a composite image. The plurality of images can be comprised of images created by exposing the sensor for different exposure times.