www.washingtonpost.com/magazine/2022/03/22/star-trek-movie-shatners-eyeball/
The iconic “retina scan” scene in Star Trek II: Wrath of Khan was not Shatner’s own eye.
It was an “eye double” software engineer.
(As the man himself says, your iPhone can take a more detailed picture these days, but it was high tech for 1982…)