chips. After implementing the CCD-dependent corrections, we median combined the dithered exposures for each field using 3-$\sigma$ rejection to create a final stacked image.

Photometric Solution
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We observed sixteen standard stars each night from Landolt (1992) to perform the [*UBVRI*]{} photometric calibration. Observations in [*U*]{} and [*I*]{}for the NE and S field were taken under slightly non-photometric conditions on the first night, but these were subsequently calibrated on the second night. The photometric conditions were similar on nights 2 and 3, allowing us to apply the average photometric coefficients from both nights to all exposures. We assumed the mean [*UBVRI*]{} extinctions for CTIO with values 0.55, 0.25, 0.14, 0.10, and 0.08 magnitudes at the zenith, respectively.

One issue to be wary of when using mosaic cameras is the possibility that the different CCDs will have significantly different zeropoints and color terms. The best way to test this is to measure the same set of standard stars on each CCD. This is extremely time-consuming, and was not practical with the Mosaic’s 2.5 minute read-out. Instead, we used nine standards on CCD2 to determine the zeropoint in each band, and assumed the CCD2 color terms measured by the CTIO staff. The 