Hi, if you intend to use the 82mm wide angle adaptor for the lee system on the TS-E 24mm II, 8-9mm of shift should be possible without any vignetting (except for the lens' own vignetting of about 1-2 stops). In case you want to use a 105mm pol filter on the lee system, vignetting starts at 9mm and becomes quite strong. The vignettiing of the pol filter is caused by the the rather long distance of the filter from the lens. The use of square filters has no influence here.