Camera transition between third person and third person aim view

Right now I am trying to do a transition between third person view and third person aim view in my Character C++ source code.

See here for an example:
Before transition:

After transition:
http://neptunegames.it/wp-content/uploads/2013/11/Ratchet-Clank-Nexus-NightmareBox-5.jpg

Right now, I am able to use a CameraBoom to do the following:
CameraBoom->TargetArmLenght = 120.f; // Reduces the player’s distance from the camera

And also orient the character toward the right direction
bUseControllerRotationYaw = true; Orients the character as I look around.

Basically, what I am missing is:
-Transition of the camera
-Offsetting the player to the left portion of the screen

Any help would be greatly appreciated

CameraBoom->SocketOffset.Y = 0.0f; // The camera un-offsets the character.

Was able to offset the character, now all that is missing is the transition animation. Id also like to set some limits to how low the character can look when aiming.