Ahh... I think I get it...
These are outside on a patio with no shade at all. They get all of the sun's rays from dawn to dusk without any protection. That's full sun, right?
so Direct sun has nothing to do with duration- it's only the exposure at any discrete moment, it has no temporal dimension? E.g. my orchids get direct sun IN THE MORNING... My christmas cactus get 'full sun' becasue they get 'direct sun' for the entire day...
