3D or 3D? That is the Question.

Sgt. Pinback
MemberOvomorphApril 24, 2012813 Views3 RepliesApologies in advance for my clumsiness in formatting and so forth. (Can't quite figure out the formatting guidelines for a start.) Apologies also if this is a repeated thread. I did a quick search but didn't spot the information I needed. So....
As a 3D virgin - my experience of that particular medium is restricted thus far to squinting (in vain) at those holograph art books that were in vogue about twelve years ago - I am keen for someone to clarify what exactly is the difference between RealD 3D and IMAX 3D, when it comes to a film such as 'Prometheus'? On which version should I be spending my hard-earned cash?
Thanks in advance!