The Lensbaby Edge 80 Optic is one of Lensbaby's "swappable" optics for its line of lenses. It has a focal length of 80mm and features a 12-blade aperture with a range from f/2.8 through f/22. It can function as a regular 80mm f/2.8 lens when facing forward on your camera, but this optic's special feature is that it allows you to employ the usual Lensbaby bend and tilt to reposition your plane of focus along any point not parallel with your camera's sensor plane.The usual Lensbaby lens tilt allows you to place the point of focus (with varying diffusion all around that point) but did not allow you to change the plane of focus itself. With this optic you can put a "slice of focus" through your image in creative ways. For example, you can highlight a certain aspect of the photo (such as producing a portrait where the eyes are in sharpest focus and everything else is softly blurred), or you can create the "false miniature" effect where the objects photographed take on the appearance of miniature scale models. The optic also has a close focus mode that will allow a close focus distance of 17".There is a bit of learning curve for this optic. Expect to play around for bit before you get the hang of it. There are some good video tutorials on the Lensbaby site. I included a couple of example photos with this review.You don't need to swap lenses to get back to "normal." As I mentioned earlier, the Edge 80 behaves like a normal 80mm lens when you aren't employing any of its tilt features. The aperture ring on the optic adjusts smoothly, and focusing and tilt occurs on the lens body itself. The shift from regular focus mode to close focus mode is a little tight -- you have to firmly pull the front edge of the optic outward. But, I imagine that's as it should be to avoid it shifting by itself.My one source of frustration so far is in detaching the optic from the lens itself. Suffice to say you will need to review Lensbaby's instructions for this, and practice several times before you can successfully detach the optic. My first try took almost half an hour, which is not a delay you would want to experience in the field. I did get better with practice, but it's still a bit of tricky. Older hands might suffer more than younger hands. I've found in practice you can get by with swapping out other Lensbaby optics from the lens without detaching the lens from your camera, but with the Edge 80 optic, you really need to detach the whole lens first in order to get the optic out of the lens. That will allow you to get the best grip on the components when performing the detach maneuver.Note that the optic in this product listing is not sold with a lens. The Edge 80 only works with the latest line of Lensbaby Lenses (NOT the 1.0, 2.0 or 3G). You need at least one of the current Lensbaby Lenses to use this optic. The optic works with the Muse, Composer, Control Freak and Scout lenses; it can also work with the Composer with Tilt Transformer, but you need to buy the Macro Converters in order to use the Edge 80 optic with that lens. Note too that if you want true macro capability, you will need to buy the Macro Converters anyway, regardless of which Lensbaby lens you have (their earlier Macro accessories will not work with this optic).Normal in-lens tilt-shift lens are expensive ($1200-$2500). While the Edge 80 does not give you all the features of such a dedicated lens, it is a highly affordable alternative that provides enough capability for many tilt/shift needs. It's a great way to get into this type of photography without breaking the bank. Highly recommend.