Canon EF 28-135mm lens
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The Canon EF 28-135 3.5-5.6 IS USM is a standard zoom lens with 2nd-generation image stabilization (IS) technology to compensate camera shake and a high zoom ratio which was introduced by Canon in 1997. The lens is based on the EF Lens Mount and will work with all film and digital EOS cameras that support this mount.
With the Image Stabilizer turned on, it is possible to obtain sharp, natural-looking pictures in dim lighting without using flash or a tripod but at the expense of double to eight times of shutter speed. While slow shutter speeds can be used intentionally, on more expensive, brighter lenses by stopping down, the relatively slow lens forces long exposure times in low light. With the second generation of Image stabilization, it is reported to be able to be handheld at 2 stops lower at the telephoto range and 1.5 stops at the wide angle range.
It features ring-type USM that drives an internal lens group for swift, silent autofocus and allows to manually tune the focus without switching out of AF mode. A six-blade diaphragm is used. Closest focusing distance is 20 in. (50cm).
The Canon EF-S 17-85MM f/4-5.6 USM gives a similar field of view on APS-C digital cameras.
Other properties:
- Front element does not rotate and the barrel does not expand or contract during focusing.
- Twist zoom action is prone to creep when pointed down.
- Distance window in meters and feet for manual focusing.
- Best sharpness starts at F/6.3 at the short-end, always centers at F8 and goes up to F11 on the far-end.
- Weakest of most of the normal zooms in the flare and ghosting discipline, the additional lens elements used for IS may contribute flare and ghosting.
- Because its Image Stabilizer (IS) is only of the 2nd generation with no tripod detection, the IE goes into an audible feedback loop (which may cause the IS to become erratic) when the lens is kept still, e.g. mounted on a tripod or held firmly in a stable grip. The owner's manual advises to turn off IS when the lens is mounted on a tripod.
Weight: 540 g (18.9 oz) Filter size: 72 mm Distortions: Small amount of barrel distortion at the wide-end and pincushion distortion at the long-end.
[edit] Specifications
| Attribute | f/3.5-5.6 IS |
|---|---|
| Image stabilizer |  Yes |
| Ultrasonic Motor | Yes |
| L-series |  No |
| Diffractive Optics | No |
| Macro | No |
| Maximum aperture | f/3.5 |
| Minimum aperture | f/36 |
| Weight | 540g |
| Diameter | 3.1" |
| Length | 3.8" |
| Filter diameter | 72 mm |
| Viewing angle | 76° – 18° |
| Groups/elements | 12/16 |
| MSRP $ | $450 |
