The smallest & lightest standard lens of its class. Its luminosity makes " Available Light" photography an absolute pleasure. It belongs to the Super performance (SP) class of Tamron lenses distinguished by ultra high optical & mechanical quality. It has very good resolution capability, strongly reduced light fall off up to the edges, minimized chromatic aberration & very good stray light behavior. Sharp & excellent pictures are the result. Furthermore, the depth of field which is rather wide due to the construction of the digital image sensors can be reduced by the big diaphragm aperture. This leads to new creative possibilities (e.g., motive stands out in front of a dramatically attractive blurred background). The designation “ Di” (Digitally Integrated Design) marks a generation of lenses, which have been specially adapted to the higher requirements of digital SLR cameras (APS-C & full frame). Please note: From June 2008 available with a „built-in“ motor in order to also serve users of new Nikon cameras which require a „built-in“ such as the Nikon D40, D40X & D60. The new version (Model A09NII) replaces the previous version (Model A09N).