How did Janus come to be emblematic of film?

[Daniel Cape]

> I figured you were asking because you'd seen others.  What DID provoke
> this question?  Just Janus Films, or ...?  "If they can get you asking

A cluster resembling this: theatrical masks, Slothrop going under,
surfacing on movie set... Janus' symbolism of 'transitions such as the
progression of past to future, of one condition to another, of one
vision to another, ... and of one universe to another' that Mark K
points out (i've got that Wikipedia feelin' all over again :).
Pynchon's use of film and other 'screen spaces' (e.g. the Tube) to
mediate and interpenetrate (mm yeah) realms (life and death in VL, for
e.g., numerous instances in GR). 's just a hunch I'm pursuing.
Doggedly... ;)

Yeah, Mark, that 'one universe to another' ref in particular tolls my
bell, too. And yes, I guess we all agree Janus Films did choose their
icon for simple marketing reasons (simple marketing reasons?!
Fuhgeddaboutit). I haven't come across any other instances, just the
annoyingly unreferenced mention in Wikipedia's 'film' article that
Janus is an icon of film, along with a 'candle and bell' icon that
Tarkovsky uses (this latter  may ring bells here; any takers?.