1. A camera comprising: a photosensor comprising a plurality of pixels configured to accumulate photoelectrons responsive to incident light, which photosensor is tiled to a plurality of super pixels, each partitioned into a plurality of pixel groups; a readout pixel configured to receive photoelectrons from the pixel groups; circuitry that operates to provide a measure of how many photoelectrons are contained in the readout pixel; and a controller configured to: transfer photoelectrons accumulated in each pixel group in a super pixel of the plurality of super pixels into the readout pixel to acquire a measure provided by the circuitry of the accumulation of photoelectrons in the pixel group; determine responsive to the measures which pixel groups have an accumulation of photoelectrons that does not saturate the readout pixel and which pixel groups have an accumulation of photoelectrons that saturates the readout pixel; and determine a measure of the number of photoelectrons in the super pixel responsive to a function of the measurements of accumulations of photoelectrons in pixel groups of the plurality of pixel groups that do not saturate the readout pixel, which function has a form determined responsive to measurements of the number of photoelectrons in at least two of the pixel groups and is independent of accumulations of photoelectrons in pixel groups that do saturate the readout pixel.