For shrooms, I've often done an eighth, and 5g twice.

Most LSD I've done was 3 tabs and several times on 2.

I mean, don't get me wrong I see some warping and tracers and extra patterns. But it's just a distortion of what's already there. Not the creation of new creatures or anything interesting with my eyes closed.

I think I'm more likely to get auditory hallucinations, as my "mind's ear" is a lot more functional.