The time-dependent response of the area detector versus column Y. (a) Pixels close to the beam stop (Fig. 4), with X coordinates as follows: left of the beam stop open squares 59, black filled squares 60, open circles 61, right of the beam stop red open squares 70, red filled squares 71, red open circles 72. At X = 60 or 71 and 65 ≤ Y ≤ 67, the intensity of the peak largely exceeds that of SANS from catalase. In this region, the phase angle (see text) for a given column number X increases by 0.95 (= 54°) on stepping from one row to the next, as indicated by the dotted line. (b) The intensity of the incoherent neutron scattering from EHBA–CrV in a protiated solvent (see Appendix A). There is little variation in the intensity with time and scattering angle. It is for this reason that a regular change in the phase angle (see text) can be observed over several adjacent Y channels everywhere on the area detector. Filled black squares: X = 40; filled blue squares: X = 41. As the systematic change in the phase angle may extend over more than 2π, each phase angle is shown three times shifted by multiples of 2π.