The Lensbaby Muse is unlike any other lens, with a bellows-like flexible lens barrel that you compress to focus the lens from 12" to infinity. Squeeze equally on both sides and the image in the center will be sharp. Compress only one side to create a zone of sharpness on that side while throwing the opposite out of focus for a dream-like effect. It's capable of delivering images with a tack sharp sweet spot of focus with minimal diffusion even at the f/2 aperture setting. Want more depth of field? Just add one of the aperture discs to stop the lens down for greater depth. Loads of fun, easily controllable, enhances creativity with 35mm and digital SLR cameras alike. FEATURES INCLUDE: high refractive index 50mm f2 doublet glass lens; multi-coated lens surfaces for improved contrast; fast aperture changing, with f2, f2.8, f4, f5.6 and f8 discs held in place magnetically; accepts interchangeable Lensbaby Optic Swap accessories.Allow 1-2 weeks delivery for Pentax, Sony/Maxxum mount lenses.