ThisLEE Filters SW150 Mark II Lens Adapteris designed to allow a separately available SW150 Mark II Filter Holder to connect to a Canon EF 11-24mm f/4L USM lens, which then permits the use of 150mm-wide, 2mm-thick filters without vignetting.
This lens adapter consists of three components, a front ring, a compression ring, and a locking ring. Placement of the lens adapter onto the lens is easily accomplished by sliding the front ring over the built-in hood with the front ring's integrated lugs positioned away from the lens body. The compression ring can then be slid over the rear of the lens until it meets the front ring. Finally, the locking ring is also slid over the rear of the lens until it can be screwed into the front ring. After that is accomplished, a SW150 Mark II Holder can then be placed over the adapter from the front of the lens for use.
Due to the possible existence of slight variations in lens construction, the following information should be viewed as a general guide and not exacting specifications.
When using two filters with the Canon EF 11-24mm f/4L USM lens and the LEE Filters SW150 Mark II system, vignetting can be avoided by setting the lens to a focal length no less than 13.5mm.
When using one filter with the Canon EF 11-24mm f/4L USM lens and the LEE Filters SW150 Mark II system, vignetting can be avoided by setting the lens to a focal length no less than 12.5mm.