The Sigma APO Teleconverter 1.4x EX DG for Canon Digital SLR Cameras is a dedicated APO teleconverter that can be mounted between select lenses and the camera body to increase the focal length by the power of 1.4. The multi-layer coating reduces flare and ghosting, which is a common problem with digital cameras. The lens also offers maximum magnification without any variation in the minimum focusing distance. Compact and lightweight, this teleconverter can convert your lenses into longer focal-length lenses, so you don't have to do a lot of unnecessary footwork. A case for the lens is included..
The Sigma 824110 1.4x DG EX APO Teleconverter for Sigma SLR Cameras will multiply the focal length of your camera's existing lens by 1.4x, and will cut back the amount of light by one f-stop. For example, on a 300 millimeter lens, this teleconverter will effectively increase the focal length to 420 millimeters, while a lens set to f2.8 will become f4. The 824110 is a dedicated teleconverter lens, and due to its high optical quality will only fit and work with a select list of compatible Sigma APO lenses, which can be determined on Sigma's website.
This lens features a new multi-layer lens coating and lens design that reduces flare and ghost, which is a common problem with digital cameras, and also creates an optimum color balance through the entire zoom range. The Sigma 824110 is constructed of five elements in three groups, weighs five ounces, and measures 2.7 x 0.75 inches (Diameter x Length). This teleconverter comes with front and rear lens caps, a soft carrying case, and is backed by a 1-year worldwide warranty with a 3-year extended US warranty.