Based on this screenshot from the article it looks like they got access to the raw film scan, before it was denoised and color corrected for the Japanese BD release. It's way grainer and way brighter. Though if any of that grain survives is yet to be seen, since despite what Funi says about preserving it their history of filtering it flat is a big source of hate for DBZ fans. What should be the same frame from the Japanese BD Box (there's 3 frames total with those cels, this one match