Tamron AF 28-75mm f/2.8 SP XR Di LD Aspherical (IF) - Review / Test Report
Lens Reviews -
Canon EOS (Full Format)
Tuesday, 03 March 2009 22:05
Page 1 of 3
Special thanks to Rainer Temme for providing this lens!
The Tamron marketing folks seem to be funny people - their primary quest is obviously
to find the longest lens names in the industry and the Tamron AF 28-75mm f/2.8 SP XR Di LD Aspherical (IF)
(did I forget something ?) is no exception to this rule here.
Thanks to its comparatively low price the lens has been very popular ever since it was released
a couple of years ago. On APS-C DSLRs it is a stellar performer but the sweet spot advantage of the crop
format makes things easy here. However, the true scope of the lens is certainly the classic full format
where it fulfills its intended role as a general purpose standard zoom lens.
Tamron used two so-called XR (Extra Refractive Index)) elements for the design. These elements bend light more efficient than normal glass thus allowing more compact lens constructions and the Tamron is certainly a dwarf compared to monsters a la Canon AF 24-70mm f/2.8 USM L or Nikkor AF-S 24-70mm f/2.8D IF-ED. The Tamron is also designated Di (Digitally Integrated) lens - this refers to an optimized lens design for image sensor characteristics.
The lens belongs to Tamron's SP (Super Performance) lineup indicating a professional grade lens by Tamron standards. However, the build quality may be good but neither the finish nor the subjective quality of the used materials are comparable to similar Tokina AT-X or pro grade Canon lenses. The zoom and focus control rings operate quite smooth. As you may have noticed in the product shots below the lens extends when zooming towards the long end. Thanks to the IF design the lens front does not rotate during zooming or focusing so using a polarizer is no problem.
The lens' AF relies on a conventional micro-motor which is good enough for an average AF speed.
|Optical construction||16 elements in 14 groups inc. 3 LD elements, 4 aspherical elements and 2 XR elements|
|Number of aperture blades||7 (rounded)|
|min. focus distance||0.33 m (max. magnification ratio ~1:3.9)|
|Dimensions||73 x 92 mm|
|Filter size||67 mm (non-rotating)|
|Other features||Zoom lock (at 28 mm).|