Hubble Frontier Field

• The HFF program (Koekemoer et al. 2016; Lotz et al. 2017) consists of multi-cycle HST observations to target six galaxy lensing clusters in parallel with six parallel blank field images (6 arcmins from the cluster core).
• HST employed 840 orbits (140 orbits for each galaxy cluster) to observe the HFF galaxy clusters, achieving a superb depth of � 28.7~29 magnitudes (5 sigma).

• Taking into account the gravitational lensing effects, the effective depths of the HFF observations are 30~33 magnitudes over very small volumes.
• For all the HFF targets, HST obtained images with the ACS and WFC3, in a total of seven broad-band �filters (F435W, F606W, F814W, F105W, F125W, F140W, F160W).