Yao Li, Ding-Peng Li, Feng-Jie Lei, Feng-Shan Liu
With the combination of deep Hubble Space Telescope Imaging and magnification due to gravitational lensing, the CLASH program offers an unprecedented opportunity to search for supernovae at high redshifts and detect some of the most distant galaxies as well. Unfortunately, the cluster field suffers from a high abundance of bright foreground sources and high background due to intra-cluster light. To overcome these difficulties, we have developed a method of modeling and subtracting bright foreground light in the clusters using Fourier analysis. In this paper, I will present preliminary results based our method, which significantly increases the effective depth of the images, and efficiently characterizes distant background signals in the clusters.