I always found this article very odd.
There's a 1963 New York Times article titled "Astronaut Plays Trick on Nasa Cameraman". You can search it on the NYT newspaper archives. It says that Gordon Cooper "whiled away the time" before his take off into space by playing a "practical joke" on the photographers for NASA. Cooper and 2 other astronauts (Schirra & Slayton) "removed the special light bulbs from the studio" in the hanger where they were normally photographed in the their "space suits".
It said they put tape on the contacts and put the bulbs back in the socket so that when the photographers arrived, the lights wouldn't work. Electricians were actually called who discovered the "prank" and fixed it. Very funny, huh? So many people would find this SO humorous when they went to try and do a job, having to then wait to find and get electricians to find out what was wrong.
Would 3 grown men really be climbing ladders taping fixtures before a space flight for a joke?
Or… was it perhaps an attempt to darken the room to obscure something? Or put someone off taking photos altogether? Dodgy spacesuits? I don't know. I just get creepy vibes from it.
They were official NASA photographers according to the article, but that doesn't mean they knew what was going on or were part of the "in" crowd. Maybe they showed up unexpectedly to take photos. Just really weird.