Thats because they are, they have a good history, they are not a Sigma, regardless of whether you see their brand being diluted in cheap SONY camera phones.
These lenses have been available for awhile now. There are aftermarket lens-kit mounts for Canon EOS that allow you to use Nikon and other lenses, although focusing must be done manually. Not so with the ones in the link you have provided, since these provide all the electrical contacts for the camera to control the lens.
... although focusing must be done manually. Not so with the ones in the link you have provided, since these provide all the electrical contacts for the camera to control the lens.
It appears the lens is manual focus. The lens has a focus ring but no motor, just like the Nikon version. Yes there are electrical contacts but not for AF.
It appears the lens is manual focus. The lens has a focus ring but no motor, just like the Nikon version. Yes there are electrical contacts but not for AF.
They are manual focus but with AF confirm beeps from the body. They have electronic aperture control and pass data back to the camera regarding this. They also work with ETTL flash metering...