Question CinemachineFreeLook How do I accurately set the X axis Angle of the main camera

It is a complex algorithm with dependencies on the FreeLook rig settings. There is no simple way to reverse-engineer this. What is the effect you're trying to achieve? Maybe there is a simple alternative.

 

Is this something you want to do in the Editor as part of authoring a scene, or is it something you expect to be able to do at runtime?

 

It would be nice to have a little more context. Do you really need to use the FreeLook, for example? Would a spherical orbit suffice (instead of the FreeLook's complex 3-rig structure)? If you're just setting up spherical orbits, then you can move away from the FreeLook and choosing angles would be easier.

 

You can try calling FreeLook.ForceCameraPosition(pos, rot). You give it the desired camera position and rotation. The camera will be placed there, and the X and Y axes get automatically set to the values that will bring the camera as close as possible to the desired pos/rot (the camera is constrained to its orbit settings). The camera will be initially positioned at the input pos/rot, then it will move to the nearest point on its orbit, either slowly or quickly, depending on the damping settings.

 

Instead of FreeLook, you can use a normal vcam with Body = FramingTransposer and Aim=POV. Then the X and Y axes of the POV will correspond nicely with the camera rotation.