ftp archive.stsci.edu and login as anonymous. cd /pub/hlsp/frontier From there you can navigate through the site to find the field and data of interest.
WGET
You can download whole directories of data using wget commands like:
wget -nH --cut-dirs=5 -r -l0 -c -N -np -R 'index*' -erobots=off http://archive.stsci.edu/pub/hlsp/frontier/abell2744/images/hst/