70s movie, group of people go into woords, directed by some special effects guy?

[halfboy]

 

I'm pretty sure the movie is from the 70's (it sure has the look and feel anyway).  I remember a group of people going on a hike, perhaps on a mountain, but with trees (but not a dense forest, more open sky).  I think they run into someone with some magic powers or something?  I think this man they run into makes a girl look at something and he seduces her/puts her under a spell.  at some point there is some kind of clay animated/stop motion dragon/dinosaur creature, but I believe it's just in their head (or due to magic).  at the end, one of the main male characters is taken away to a padded room/insane asylum.  That's about all I remember.  And I think the person that directed it was somebody's special effects director.  Like they did special effects at some point for some one big (like Spielgberg)

Thanks!

[Rayo Casablanca]

EQUINOX (1970) http://www.imdb.com/title/tt0067055/?ref_=fn_al_tt_2

[M.10rda]

The description matches EQUINOX, don't think there's another movie like it. This is probably Solved...