The recording of holograms in which the reference beam enters through the supporting substrate involves attenuation factors which differ strongly between signal and reference. This paper addresses the issue of fringe contrast under these extreme conditions and provides quantitative data that are indicative of at least a partial solution to the problem. We define a spatial average for the fringe contrast and offer results which follow our theoretical model for Du Pont OmniDex$+TM$/ photopolymers. The direct edge referenced technique for recording is re-visited with observation of a new phenomenon which we call self-induced index matching. An alternative fringe recording geometry is proposed and compared with direct recording.
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