Change Camera Distance As Rotation Changes

I'm trying to recreate the same effect as the Cinemachine Orbit Rigs.

As the camera rotates up or down its distance to the player decreases.

I know it should be something along the lines of as the rotation value increases the distance decreases with a little lerp to smooth it out but I'm missing something.

Point me in the right direction as my brain is a little fried at the moment.

Thanks!

 

If I understand your description, you can kinda get this for free if you pivot an extra Transform AT the player's location, and then offset based on that Transform to drive your camera location, making the camera effectively stay within a sphere around the player.