Parameters are accessed with C4DAtom::GetParameter()/ C4DAtom::SetParameter(). See Parameter IDs.
Parameter: Camera Type
REDSHIFT_CAMERA_TYPEParameter: FOV
REDSHIFT_CAMERA_FISHEYE_ANGLEParameter: Horizontal Scale
REDSHIFT_CAMERA_FISHEYE_SCALE_XParameter: Vertical Scale
REDSHIFT_CAMERA_FISHEYE_SCALE_YParameter: Orthographic Cylindrical
REDSHIFT_CAMERA_CYLINDRICAL_ORTHOGRAPHICParameter: Horizontal FOV
REDSHIFT_CAMERA_CYLINDRICAL_FOVHParameter: Vertical FOV
REDSHIFT_CAMERA_CYLINDRICAL_FOVVParameter: Orthographic Height
REDSHIFT_CAMERA_CYLINDRICAL_ORTHOGRAPHIC_HEIGHT