Identification of variable objects with three different methods for the filters R and I. The diagrams on top and in the middle show the amplitude and S D methods respectively. For both methods, the threshold varies exponentially because the scatter and noise are higher for weak objects. The lower diagrams show the J–index method. We established an empirical threshold of 1.35 after conducting a detailed examination of the light curves for variable candidates that were also detected using other methods. This threshold was further refined by eliminating spurious detections.