This Tamron's ultra wide-angle zoom lens starts at 17mm when used with a conventional 35mm SLR camera. When mounted on an APS-size digital SLR camera, it provides a focal length coverage equivalent to a 28-55mm (on a 35mm format camera), covering the desirable wide-angle to standard range.
It has maximum aperture F2.8 at 17mm and F4.0 at 35mm. Being F2.8 at wide end is an advantage for this lens compare to other wide angle lenses. It has 77mm filter which is very usefull for a wide angle lens to prevent vignetting at wide end. The spherical front element will cause some flare but can be correct easily by using a petal type lens hood that come with the lens.
Specifications
| Image Circle | : 35mm |
| Focal Length | : 17-35mm |
| 35mm Equivalent | : 25.5-52.5mm |
| Max Aperture | : F2.8-4 |
| Min Aperture | : F22 |
| Diaphragm Blades | : 7 Blades |
| Lens Construction | : 14 elements in 11 groups |
| Angle of View | : 104 to 63 degrees |
| Focus Details | : Internal |
| Front Element Rotation | : No |
| Zoom System | : Rotary |
| Closest Focus | : 0.3m / 0.98 ft. |
| Magnification Ratio | : 0.19x / 1:5.4 |
| Filter Size | : 77mm |
| Dimensions | : 86.5mm x 83.2mm / 3.4 in. x 3.3 in. |
| Weight | : 440g / 14.4 oz |
1. Build Quality
The build quality is satisfied me and feel solid in my hands. The build seem better than other tamron lens and not feel plasticky. The weight and the size is quite acceptable for the wide angle lens. This lens come with a huge petal type 77mm hood to prevent flare.
This lens extend when zooming but it just extend around 1cm and not really noticable. This lens feature Internal Focus[IF] which prevent it extend or rotating while focusing. The picture below show the size comparasion of the lens when extend.
2. AF Mechanism
This lens AF is quite faster. The AF sound is a little bit noisy but still acceptable and not annoying me. The accuracy is good for a close range object at all focal length but sometimes it missfocus when the subject range is too far especially at 17mm and wide open. 3. Image Quality(IQ)
This lens is very sharp even at wide open and extreme sharp if you add 1 or 2 stop exposure. The center sharpness was really impressive but the corner sharpness is drop drastically but still acceptable.
4. Distortion and Vignetting
At 17mm, this lens show visible distortion but there is no distortion from 24mm and above.
5. Chromatic Abberations(CA)
6. Conclusion
For the conclusion, overall I found that this lens is very worth for the money I paid. Here are some samples that I took with this lens. I will add some sharpness and resolution test in the future for reference.
7. Rating
| 1. Optical Quality | ★★★★ |
| 2. Build Quality | ★★★★ |
| 3. Value for Money | ★★★★☆ |
HIGHLY RECOMMENDED
