http://lensbaby.com/product/composer-pro-ii-with-edge-50-optic/ Canon EF Mount/Full-Frame Format Compatible with Optic Swap System Metal Body with Tilt from 0-15° Flat Field Optic Creates Slice of Focus Aperture Range: f/3.2 to 22 Manual Focus and Aperture Control Minimum Focus Distance: 8" Filter Diameter: 46mm Internal 9-Blade Diaphragm #YearStartsHere