Sacred Mirror of Kofun

Hints:
———
On each of your dives, you need to take a specific number
of photographs for later bioanalysis. Be sure to listen to
your computer, which will advise you when to click the shutter.
Those bottles floating by aren’t trash. Snag and inspect them.
                         
That beeping sound may not be water in your ears: it could
be Morse code. To decipher it, check out the manual on the
shelf in your cabin room.