1. A camera comprising: a photosensor comprising a plurality of pixels that generate and accumulate photoelectrons responsive to incident light, which photosensor is tiled to a plurality of super pixels, each partitioned into a plurality of pixel groups; optics for imaging light onto the photosensor; a readout pixel that receives photoelectrons from the pixel groups; circuitry that provides a measure of how many photoelectrons are contained in the readout pixel; and a controller that provides a measure of a number of photoelectrons in a super pixel responsive to quantities of photoelectrons from pixel groups in the super pixel that do not saturate the readout pixel.