According to Osho, you distinguish projection from authenticity by effort after the event: a projected experience demands constant mental feeding - remembrance, affirmation, imagination - and collapses the moment you stop, like a film when the projector halts. An authentic realization needs effort only before; once it happens it abides effortlessly - awake, asleep, remembered or forgotten - the tree never again becomes 'just a tree'.
If you have to keep reminding yourself for it to feel real, it’s a projection; the real thing stays real even when you forget it.