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Gravitationally lensed QSO's have become important astronomical tools for a wide range of astrophysical problems. They provide tests of General Relativity and act as probes of intergalactic matter. They may allow direct estimates of the Hubble constant from time delay measurements and could be used to estimate dark matter in galactic halos. HST (PC) images of gravitational lens systems should provide improved measurement of positions and fluxes of the QSO images, and may allow detection and possible characterization of the lensing galaxies. However, the HST point spread function makes accurate parameter extraction more difficult. We have found that measurements made from the power spectra of these relatively simple objects provides improved accuracy and, in some cases, the discovery of features not obvious in the raw (or deconvolved) images.