RDJ: Toughest part in being Iron Man are the close-up shots.

In an exclusive interview with Yahoo! Movies, in preparation for the release of the second Iron Man 3 trailer, Robert Downey Jr. says the toughest part of playing Iron Man is filming scenes with the “Heads Up Display” view, which allows viewers to see Downey’s face up close whenever Tony Stark dons the metal suit.  

From Yahoo:

“When you do the HUD work, usually it’s kind of the last thing in the schedule,” Downey said. “And you’re going back and essentially living the movie again in close-up, tired.”

Basically, Downey has to relive all of the action scenes in the movie they already shot and deliver the same level of intensity even though he’s standing still and there’s nothing for him to actually react to. That includes performing some of his most emotional scenes, like in The Avengers when he is unable to contact Pepper (Gwyneth Paltrow) while he is flying to what he believes will be his death.

Downey explained it this way:  “I don’t like, [as himself] ‘All right. What’s happening now?’ [as the director] ‘Oh, the most important woman in your life is falling off crane into a fiery pit. Okay? So, let’s just rehearse once and then we’ll do it about 10 or 12 times until the camera is right and you’ve given enough.’ They’re just screaming direction at you… I like the scenes. I like the action.”

(Source: Yahoo!)