A quick Test according to Rampas suggestion...
Used "Antenna01" from Template Folder "Spring", attached to my character, camera look at "Spring04"...
Antenna scaled in Z-axis to 300, spring sliders:





Toystorylab on Vimeo :     Crassitudes (my "Alter Ego") on Youtube: 

I'm itching to get to iClone but so much to do.
One thing I want to try is what if the antenna itself was the look at and parent to the camera.
I never tried a spring as a twisting effect. I guess it would have to be tiny to limit its effect.
I think this idea might have some weird side effects.
 

This is beautifully simple I gotta try this.

I also think the most realistic "Hand-held Camera" would be the approach of René aka "the director1974" (ALIEN - the Message) as 4u2ges mentions...
But surely will need a bigger amount of work, will be more elaborate/lavish to do so.
The approach of Rampa is interesting and i will try this out in the next days...


Toystorylab on Vimeo :     Crassitudes (my "Alter Ego") on Youtube: 

Here is the same clip, but with a rotational spring. Also a bit more extreme on the sliders.

So this is with the default spring of the antenna thingymabob. It's a linear spring. That means the bones only move on X and Y. You can also set the spring to rotational in 3DX. Then it gets pretty drunk looking. There is a lot of variability adjusting the three spring sliders. This one is pretty tame, with no bounciness. Left it visible to show what's going on. Camera is targeting the sphere.

>@4u2ges I don't know what you are trying to explain.<

What I have shown is a concept. Idea was not mine. I saw it first when thedirector1974 implemented it in his Alien clip. That was a brilliant walk into the command center.

https://forum.reallusion.com/FindPost361116.aspx
https://forum.reallusion.com/FindPost362530.aspx

OK, you said you do not want to have a robotic camera behavior. But the constrain (delay or no delay) gives you exactly that. Camera does point to one specific bone and following it with robotic precision. And if you have a delay with second invisible character, it is going to be a precise delay. Sometimes a camera man is trying to predict the next actor' movement and pan the camera in that direction. Now you have an advance instead of delay. Sometimes he does "overshoot" - trying to follow but gets slightly ahead. I do not see any way of doing that in iClone unless you manually key it and add an element of randomness. Spring by Rampa might work, but I want to see it.
My idea was, first to add a *shaky randomness*. If cameraman is holding a camera and is trying to following the subject there would always be a subtle shaking in all direction. So I attached a camera to a character spine, applied an idle motion to the character (you do not see that character because he is "holding" a camera).  There are plenty of different idle motions are out there, from subtle to energetic (subtle would work best I suppose). They can be extended, looped, smoothed.. etc. Once you have that in place, you begin animating the *camera* by rotating the torso of the *cameraman*, or moving him for panning, or he can even walk as thedirector1974 made him to. You roughly point the camera toward the actor on a timeline and the idle motion would do the job of delaying, overshooting, etc. Or you can do that with transition curves for the *cameraman* motion keys as you see it appropriate. Lot of work? Maybe. So feel free to use it of dump it :)

Guess I didn't think that one through well enough!

I thought some sort of automatic rig would be more interesting too. The target on the spring chain was the the first thing I thought of.

A looking at camera has no keys.
What?

Probably easiest just to set an ease-in transition curve on the constraint key for the camera, but it's not automatic.