A method of determining a normalized quantity of an analyte adhering to beads in a detection area of a bead-based assaying system, the method comprising: a) causing a complex of the analyte to fluorescently or chemically emit a first light, or to release a dye; b) measuring an integrated intensity of the first light emitted from the beads in the detection area, or a concentration of the dye released from the beads in the detection area, or both; c) causing light to interact with the beads in the detection area, the interaction not depending on whether or how much analyte is adhering to the beads; d) measuring a second light resulting from the interaction with the beads which does not depend on the analyte; and e) determining the normalized quantity of analyte from the integrated intensity of the first light or concentration of the dye or both, and from the measured second light.