Tokina AF - Focal Length: 80 to 400mm - Maximum aperture: f / Camera Lens /4.5-5.6 - Minimum aperture: f/32 - Optical construction: 16 elements in 10 groups - SD glass: One elements - Zooming system: Rotary type - Filter size: 72mm - The latest AT-X 840D is still the smallest lens to zoom to 400mm with a...