The reason you can’t take pictures: “The real reason actually goes back to 1980, when Vatican officials decided to begin a large scale, comprehensive restoration of Michelangelo’s art in the chapel. The cost was huge. So huge that they searched for third party to help pay for the project. The highest bidder was Nippon Television Network Corporation of Japan, with a $3 million offering (costs eventually increased to $4.2 million).
In return for funding the renovation, Nippon TV got the exclusive rights to photography and video of the restored art. Along with that, all photos and recordings of the actual restoration process could only be done by photographer Takashi Okamura, who was commissioned by Nippon TV.”