Teleconverter for Video?

While going thru some of my camera gear I stumbled across an old Vivitar .43 Wide Angle Teleconverter. Sice I already had my Canon 28mm FD Lens on my Sony I decided to shoot some video with it to see if it's useable , the results shocked me frankly. I don't think I'd use this for Stills but seems quite useable for video. Some Footage of the Teleconverter in action