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. No 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. The front lens is fixedThe fixed front lens is not rotating during zoom and/or focusing. This allows the photographer to use petal shaped lens hood. Fixed front lenses also make the use of polarization filters a lot easier. 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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The AT-X 235 AF PRO is a wide-angle zoom lens that will produce dynamic images, which are sharp from edge to edge. The fast, constant maximum aperture of f/2.8 makes wide-angle photography, like reportage, effortless in difficult lighting situations such as indoors or at dusk.
Two Pioneering all-glass aspherical lens elements, one front and rear, (F&R aspherical) are employed to eliminate wide-angle spherical astigmatism and correct edge/marginal light rays for superb image quality. Hoya Corporation, the world?EURTMs largest optical glass manufacturer, has created a micron-tuned precision molding technique with the accuracy to form aspherical surfaces to the thousandths of a millimeter. These aspherical elements, as well as 11 more of the remaining 13, receive Tokina?EURTMs unique multi-coatings to further improve optical performance. |
Available mount(s) | Canon EF, Nikon F, Sony / Minolta A |
Application(s) | Landscape, Interiors, Architecture |
Category(s) | Wide angle zoom |
Multiplier | 1× |
Stabilizer | no |
Focal length | 20 - 35 mm (1.8× zoom) |
Lens construction | 15 elements in 11 groups |
Angle of view |
35mm: 93.6-63.2° digital: N/A |
Number of blades | 8 |
Maximum aperture | wide: f/2.8 tele: f/2.8 |
Minimum aperture | wide: f/22 tele: N/A |
Minimum focusing distance | 25 cm |
Magnification | N/A |
Filter size | 77 mm |
Size | ∅ 84 × 85.5 mm |
Weight | 585 g |
Notes |
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AF speed | N/A |
AF sound | |
Internal focusing | yes |
Internal zoom | N/A |
Fix front lens | yes |
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 | no |
Hard case | N/A |
Soft case | included |
Lens hood | included |
Tripod adapter | N/A |
Discontinued | yes |