I did a long event Friday with my LS-300 and HM-200 on tripods. Even though the tripod heads were carefully leveled I noticed in post that footage from both showed a definite cant, which was easily correctable. Both cameras were mounted to the tripod via Arca-Swiss plates attached to the tripod mount. When I looked carefully at the plates it was clear that they were slightly canted due to the bottom of the camera being slightly rounded. I will shim the plates to make them level, but it seems strange to have to do so. Anyone else seen this?

I experienced a similar problem with a Panasonic camera. I stopped using the tripod head's bubble level. If I was shooting indoors, I would focus on a door frame and line up the door frame with the camera's LCD frame markers to level the camera. There are small bubble levels that you can mount in your camera's hot shoe and use it to level the camera. B&H stocks a wide variety of camera bubble levels.

I shimmed both arca-swiss plates with a strip of gaffers tape. Now when the fluid head is level the cameras are as well :)