Kiss and collaborators. These observations in $V$ and $I_{\rm c}$ were obtained with the Siding Spring Observatory 40-inch telescope, helping to reduce the gap between the Mount Stromlo and the CTIO data set.

For a different project (Lebzelter et al.[@LWHJF05]), we did a short photometric monitoring of some parts of 47 Tuc with ANDICAM at CTIO’s 1.3m telescope in March to May 2002. These data were obtained in the $V$-filter with the old ANDICAM CCD which had severe limitations (only half of the chip was useable). These data were used only in rare cases.

Data reduction
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For the Mount Stromlo and the CTIO data, flatfield and bias correction was done as part of the standard data pipeline. The 40inch data were reduced applying standard data reduction with MIDAS, while the WFI data were reduced with the corresponding IRAF package. For the detection of variables and the measurement of the light curves on the Mount Stromlo and CTIO frames we used the image subtraction code ISIS 2.1 by Alard ([@alard00]). First, the two data sets were analyzed separately. The reference flux of the identified variables required to produce light curves from the image subtraction measurements was derived using the PSF 