SPOILER! Kattints ide a szöveg elolvasásához! Why Hulk went from being out of control to being in control. (spoilers)
I see a lot of people confused by this, but the movie actually explains it well.
When he hulks out the first time (out of control):
- He wants to avoid turning into the Hulk.
- He made it very clear that he didn't want to be involved directly.
- Just before transforming, he blamed Black Widow for dragging him into it.
- His thought process was influenced and his rage was amplified by Loki's spear.
- After the explosion at the helicarrier, it became clear that he was indeed going to be directly involved--something that he really did not want--his anger became too much for him to control.
- Hulk's anger was mainly directed at Black Widow, which is again because he blamed her.
- Hulk later attacks Thor because Thor attacked him first.
- This all results in Banner turning into an extremely savage Hulk due to his uncontrollable rage as evidenced by his involuntary transformation.
When he hulks out the second time (in control):
- After the old man confirms that Hulk purposely aimed his landing away from any civilians, Banner starts to consider Stark's earlier words about Hulk being concerned when it comes to saving innocent lives. He is now alright with transforming into the Hulk.
- Banner has forgiven Black Widow and completely come to terms with being dragged into it after learning to trust Hulk.
- Bruce's rage is no longer channeled towards his own teammate, but instead, he channels his rage towards the aliens the same way he channeled it against Abomination in The Incredible Hulk.
- Hulk holds a small subconscious resentment against Thor for their earlier scuffle, which is why he punched Thor.
- This all results in Banner turning into a Hulk that works with the team due to the fact that Banner willingly transformed through controlled rage as evidenced by the controlled transformation.