In order to examine inter-night and long-term optical variability trends more clearly, we have generated a compressed version of the DLCs, integrating just the data acquired during the first and the last hour of observations on each night. This gave two data points per night (excepting a couple of cases when the entire duration of observation was less than two hours and therefore only one data point could be obtained). The above integration typically involved 3-4 data points in B and V, and 5-6 data points in R and I passbands. The compressed DLCs are shown in Fig. 3.
|Figure 3: Compressed DLCs generated from the profiles shown in Figs. 1 and 2. These DLCs represent only the data acquired during the first and the last hour of the individual nights. In order to enhance clarity, we have applied fixed offsets of 0.45, 0.0, -0.2 and -0.35 magnitudes, respectively, to the B, V, R and I-band DLCs of the blazar. The corresponding offsets for the DLCs of the comparison stars are 0.1, 0.0, -0.1 and -0.25 magnitudes, respectively. Note that the gap in the R and I data of UPSO on March 19 and 20 has been filled using the VBO observations, since one of the comparisons star 1 was common to the two datasets|
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