I actually had i CIM on East Coast Beach about 3am several years back. But realsied when walking back others would be able to see us clearly ...
As you are on the beach and looking back towards land (dark) it is quite dark so think that it will be same for people looking at us, but then those on that side looking at sand would be able to see clearly what we were doing, especially with moonlight ... anyway, was young that and in the midst so small head too strong liao