Wavefront shaping methods by spatial light modulators, have been an invaluable tool for a plethora of applications in photonics of complex media [1]. In fact in a series of ground-breaking experiments, reverse propagation by phase conjugation was used to create tight focusing of light inside complex media and multimode optical fibers [2], [3]. Here we addressing the problem of tight focusing in multimode fibers, in the context of non-Hermitian photonics [4], [5], by relying on singular value decomposition (SVD) techniques.