The 1993 Laserdisc was sourced from the negative, as was the UHD. In terms of image quality, the UHD beats it for sure. Not sure about color though.
For its Ultra HD Blu-ray release, Universal remastered Scarface from the original 35mm film elements, and Its presentation in Ultra HD appears to be derived from the 4K Digital Intermediate.
Have you seen the 93 LD