  The recent increase in well-localised fast radio bursts (FRBs) has
facilitated in-depth studies of global FRB host properties, the source
circumburst medium, and the potential impacts of these environments on the
burst properties. The Australian Square Kilometre Array Pathfinder (ASKAP) has
localised 11 FRBs with sub-arcsecond to arcsecond precision, leading to
sub-galaxy localisation regions in some cases and those covering much of the
host galaxy in others. The method used to astrometrically register the FRB
image frame for ASKAP, in order to align it with images taken at other
wavelengths, is currently limited by the brightness of continuum sources
detected in the short-duration ('snapshot') voltage data captured by the
Commensal Real-Time ASKAP Fast Transients (CRAFT) software correlator, which
are used to correct for any frame offsets due to imperfect calibration
solutions and estimate the accuracy of any required correction. In this paper,
we use dedicated observations of bright, compact radio sources in ASKAP's low-
and mid-frequency bands to investigate the typical astrometric accuracy of the
positions obtained using this so-called 'snapshot' technique. Having captured
these data with both the CRAFT software and ASKAP hardware correlators, we also
compare the offset distributions obtained from both data products to estimate a
typical offset between the image frames resulting from the differing processing
paths, laying the groundwork for future use of the longer-duration, higher
signal-to-noise ratio data recorded by the hardware correlator. We find typical
offsets between the two frames of $\sim 0.6$ and $\sim 0.3$ arcsec in the low-
and mid-band data, respectively, for both RA and Dec. We also find reasonable
agreement between our offset distributions and those of the published FRBs.
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