You cannot shoot DV25 uncompressed- there is no such thing. The compression happens in the camera. You could run the S-video signal out to an uncompressed capture deck such as a Kona but I’d debate whether the trouble involved would produce a notable increase in signal quality. May I suggest going to camera capable of shooting a higher quality format- such as an HVX200 or an SDX900. The increase in cost to carry another person and an uncompressed capture system would easily offset the rental of one of these cameras.
Noah