Lensbaby The Muse Double Glass for Canon EF mount Digital SLR Cameras Compress the lens to focus, and move the sweet spot by bending the flexible lens tubing. Features the Lensbaby Optic Swap System Magnetically suspended disk aperture system allows f/2.0, f/2.8, f/4, f/5.6, f/8.0 aperture settings. All aperture settings included. 37 mm threads allow you to attach Lensbaby Macro Kit lenses, wide angle and telephoto conversion lenses, and other filters and accessories Note: a Lensbaby does not communicate electronically with your camera body