As for the vibration, if this is caused by the target position moving around, then here is a solution. For the dynamic camera movemovent when it follows something you can use a threshold.
Lets say it's following the player, and the player move to the right by 2. The camera is a dead zone that is 10. You check the camera position to the target position and if it's off by more than 10, you move the camera at the edge of that 10. And it works in all directions, so until it passes that certain range, the camera will not move.
Depending on the reason for your jitter, this might work for you. It worked for a character I had, that the camera was targetting a node mounted to the character, and the character's collision squares where mounted to the feet. As the animation moved around, I had a jitter in the camera. Using this dead zone fixed that problem. When the character would walk without the dead zone, the camera had an annoying up and down motion. With the dead zone it stayed fixed.
The dead zone does mean that it will have a delay before it starts following the target. But it makes a more pleasing camera.
