I saw it nestled in the Haight - the original bedroom of psychedelia.
It's best to follow these directions at night. At the beginning of Delmar (hint), look due North at the lovely little church. You'll see a piece of stained glass which has many things to appreciate. But our special effect requires precise alignment (of both the body and mind) -
Now - look into the light. Relax your eyes, and try to detect the faint motions that your eyeballs are almost always doing - darting quickly back and forth. This may produce an acute sense of depth - the circle in the center of the stained glass window may pop into a shimmering sphere surrounded by red stars hovering over an intricate interlacing of deep blue and green.
Keep your eyes out here for a simulation of this effect.
And read on:
The Rose Window