I'm in the process to receive a lens for my Beaulieu 6008 and I'd like to know if all C-Mount lenses have to be collimated or, in the case of lenses that are not actually screwed on but are equipped with a ring which "fastens" the lens to the body (llike the standard Schneider or the Angenieux 6-90 with LCU), such a process may be waived; in fact I suspect the different way the lens is attached to the camera makes it impossible to have microscopic variations in the rear element-to film plane distance which usually accounts for the need of collimation.
Or, is there a way to assess if a lens actually needs collimation? Possibly by shooting some feet of film? I guess with rather poor light so as to have the iris work at maximum aperture AND the focal length set at the widest. How does it sound?