Full frame sized imageLenses that create APS-C sized image are designed for digital only. They cannot be used on cameras that have image sensor larger than the APS-C format. These lenses are not suitable for film cameras either. No Ultrasonic AFLenses with ultrasonic focusing mechanism tend to be quiter and faster than traditionally focusing lenses. No stepping motor AFLenses with stepping motor focusing mechanism are better for contrast based focusing, and are quiter and faster than traditionally focusing lenses. One or more Low Dispersion lens element is usedLow Dispersion lens elements help to reduce chromatic aberration. Not stabilizedImage stabilization helps to reduce blur caused by hand shake, especially at high focal length or in low light situations. Image stabilization can give 1 to 3 stop advantage over none stabilized lens, based on the reciprocal rule. Metal mountCheaper lenses are usually equipped with plastic mount, while more expensive, professional lenses have metal mount. In general, metal mounts are more durable, and a good thing to have when lenses are changed a lot. When a camera is used mainly with one lens, the material of the lens mount is not that important. Internal FocusingInternally focusing lenses don't change their size while setting focus. No Internal ZoomInternally zooming lenses don't change their size while focal length is changing. No drop-in filter supportDrop-in filters are used in those lenses where either the front lens is too large, or the field of view doesn't permit the use of traditional filters at the front of the lens. Usually bright tele and ultra-wide angle lenses support this filter type. |
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Still the smallest SLR lens available that zooms to 400mm, the AT-X 840 AF D has a smooth and quick internal focusing system that means the all-metal inner barrel that houses the heaviest glass elements does not have to rotate when the lens focuses, making it much faster than the previous models. Optically, the AT-X840 AF D has new multi-coatings applied to the elements that are formulated to compensate of the highly reflective CCD and CMOS sensors in today?EURTMs Digital SLR cameras. The new multi-coating greatly reduces the chance of internal flare or ghost reflections. A built-in low-profile tripod collar makes for a well-balanced camera/lens combination when using a tripod or monopod. The AT-X 840 AF D an excellent traveling companion is the zoom lock switch. The zoom can be locked at 80mm to so there is not chance of ?EURoezoom creep�? when the camera and lens are being carried over the shoulder. No more removing the hood to change the position of the filter.
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Available mount(s) | Canon EF, Nikon F |
Application(s) | Portrait, Landscape, Wildlife |
Category(s) | Tele zoom |
Multiplier | 1× |
Stabilizer | no |
Focal length | 80 - 400 mm (5× zoom) |
Lens construction | 16 elements in 10 groups |
Angle of view |
35mm: 29.16-16.26° digital: N/A |
Number of blades | 8 |
Maximum aperture | wide: f/4.5 tele: f/5.6 |
Minimum aperture | wide: f/32 tele: N/A |
Minimum focusing distance | 250 cm |
Magnification | 0.19× |
Filter size | 72 mm |
Size | ∅ 79 × 136.5 mm |
Weight | 1020 g |
Notes |
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AF speed | N/A |
AF sound | |
Internal focusing | yes |
Internal zoom | no |
Fix front lens | N/A |
Mount type | metal |
Weather sealed | N/A |
Drop in filter | no |
Ultrasonic AF | no |
Stepping motor AF | no |
APS-C sized circle | no |
Low dispersion lens element | yes |
Hard case | N/A |
Soft case | N/A |
Lens hood |
BH-725 printable lens hood |
Tripod adapter | N/A |