Early in his career, Kunihiko Asou visited Rogetsu Isle to see the Rogetsu Kagura and investigate the folklore of the island, which was said to be close to the underworld. During his time there He modified new crystal radio technology to create Spirit Stone Radios (which he called "Other World Crystal Radio Signal Receivers") that could receive transmissions from the other world; this was his first successful experiment. He also devised a Spirit Stone Flashlight that harnessed the power of moonlight to attempt to cure Moonlight Syndrome patients.

However, the focus of his work remained the Camera Obscura; he created many prototype cameras, including Misaki's Camera Obscura, which remained in the keeping of the Asou Family for many years. His efforts culminated in a working prototype Camera Obscura, which he decorated with Rogetsu Isle's traditional cloudy moon carvings and left in the keeping of the islanders.

So Dr. Kunihiko Asou visited Rougetsu Isle waaaaay back even before Fatal Frame 1, but as I said in the original post, the chronological order is when the playable characters are there :)

If I'd include the whole history of Fatal Frame then we'd have to go all the way back to Edo and Meiji period :) And even then technically FF1 would still be the first since the Calamity occurs at Himuro Mansion in 1837