How are the Iron Man suit scenes filmed?

Question

In all three movies, you see Downey Jr (as Tony Stark, and occasionally Cheadle as Rhodes/War Machine) in the namesake suit, either completely covered, or with the head open or having the suit put on/taken off.My question is what kind of filming techniques were used in order to achieve this feat of seamless transition from ordinary man to Iron Man?

Answer 1

In the Iron Man films, there were practical suits (and pieces of suits) that the actors could wear. The team responsible for working on the CGI would be able to use the real suits as reference for the CGI replacements or additions. It made it easier for the both the actors and editors to have something practical to work off of.