According to multiple reviews from Blu-ray.com and The Digital Bits , the standalone release from (released September 18, 2018) features the following technical details:
: 1080p High Definition presented in a 1.78:1 aspect ratio (opened up slightly from the original 1.85:1). Phantasm IV - Oblivion [HD] (1998) Bluray 1080p...
The (1998) 1080p Blu-ray is widely regarded by reviewers as a "bridge" entry in the series, notable for its dreamlike, contemplative tone and its unique use of archived footage from the original 1979 film. Blu-ray Technical Specifications According to multiple reviews from Blu-ray