  The Advanced Camera for Surveys (ACS) Virgo Cluster Survey is a large program
to image 100 early-type Virgo galaxies using the F475W and F850LP bandpasses of
the Wide Field Channel of the ACS instrument on the Hubble Space Telescope
(HST). The scientific goals of this survey include an exploration of the
three-dimensional structure of the Virgo Cluster and a critical examination of
the usefulness of the globular cluster luminosity function as a distance
indicator. Both of these issues require accurate distances for the full sample
of 100 program galaxies. In this paper, we describe our data reduction
procedures and examine the feasibility of accurate distance measurements using
the method of surface brightness fluctuations (SBF) applied to the ACS Virgo
Cluster Survey F850LP imaging. The ACS exhibits significant geometrical
distortions due to its off-axis location in the HST focal plane; correcting for
these distortions by resampling the pixel values onto an undistorted frame
results in pixel correlations that depend on the nature of the interpolation
kernel used for the resampling. This poses a major challenge for the SBF
technique, which normally assumes a flat power spectrum for the noise. We
investigate a number of different interpolation kernels and show through an
analysis of simulated galaxy images having realistic noise properties that it
is possible, depending on the kernel, to measure SBF distances using
distortion-corrected ACS images without introducing significant additional
error from the resampling. We conclude by showing examples of real image power
spectra from our survey.
