Well, my experience was that at first, I didn't see the forks at all. (That is to say I didn't recognize them as "forks". Or even as "things".) The forks looked like some blurry, nondescript background and the "pepper shapes" looked like foreground items hanging from something unseen off the top. The shapes didn't look really like anything I could identify. That lasted for a good 30 seconds before, very (very) suddenly, it crystalized and I could only see the forks on a purple background. Really uncanny how rapidly and entirely it shifted. After a good amount of effort, I was able to shift back to the first perception, but it took considerable effort along with looking away and back a couple of times. And once I achieved it, it felt hard to maintain. Very strange experience. Far more so than most "bistable" sort of optical illusions I've seen.