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We have extracted for further analysis a set of nearly 100 galaxies from 11 HST Wide Field Camera images as part of the Medium Deep Survey (MDS) Key Project program. This sample reaches I $\sim$ 20.5 and complements other fainter galaxies analyzed by the MDS team. In addition to standard processing steps, an improved set of flat field frames were applied before deconvolving the data and extracting quantitative measures. We have measured various photometric and structural parameters, including total magnitudes, half-light radii and surface brightnesses, bulge to disk ratios, and disk and bulge scale lengths. Moreover, the deconvolved images were used for morphological classification of the galaxies and to identify unusual structures or close neighbors. We compare the morphologies of our brighter galaxies to that of fainter galaxies, including the degree of central concentration and symmetry, and the frequency of more complex structures. We also test the observed half-light radii versus magnitude relation to that from model estimates that incorporate a range of cosmologies, luminosity evolution, and exotic processes such as mergers or disappearing dwarfs.
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