Color-composite images of the nine cluster center fields presented in this work (for the 10th field, i.e., MACS 1149, see Figure 1 of Wang et al. 2017). The blue, green, and red channels are stacked images from the HFF/CLASH mosaics taken at various filters, shown to the right of each panel. The footprints of HST WFC3 near-infrared grism pointings are denoted by the red and green squares, with the corresponding wavelength dispersion directions marked by the arrows in the same color in the upper right corner. The cyan contours represent the critical curves at the sample median redshift (z = 1.63) predicted by our default macroscopic lens models (see Section 3.6). Our sources with sub-kpc resolution metallicity gradient measurements are marked by magenta circles.