THE MICROVARIABILITY CHARACTERISTICS OF OJ287

We present the results of the study of visible (UB-VRIZ) intra-night m icrovariability in the blazar OJ 287. Useful observations (at least fo ur integrations in a single band in a single night with a single teles cope) were carried out on a total of 26 nights from November 1993 to N ovember 1994. Relative photometry was taken against star 4, 10 and 11 of the standard sequence, principally in the Johnson V filter, using 8 2 cm, 1 m and 2.56 m telescopes in Tenerife and La Palma. Globally, 73 % of the nights show microvariability. We find strong indications of a n anticorrelation of the amplitude of variability with the brightness of OJ 287 for quiescent activity. The lesser quantitites of data in ot her bands limit our ability to differentiate clearly between different models for the generation of microvariability. Our observations sugge st though that at least three different mechanisms may be responsible for the observed characteristics of the light curve at different epoch s.