found 'em! posters my dad brought back from san francisco in summer 1966 (&, as an art student, thought to keep them flat), part 1. some BGP classics.
posters my dad brought back from san francisco, summer '66, part 2, family dog edition (plus a stray BGP)
@bourgwick love the Sir Douglas Quintet poster, the copy I have has a slight offset in the green print which gives a really nice feel.
@doc_dead i think the offset is meant to simulate 3D? or maybe just an accident?
@bourgwick I always assumed it was a serendipitous accident. Cool effect whatever.
Also have a copy of the PH Phactor poster, but I think mine has a brown/orange second layer. Will dig it out.