Tamron 90mm f/2.8 Di Macro 1:1 VC USD SP
I purchased this lens to use with my Sony A57 (16.1 megapixel APS-C, 1.5x crop). I have three other Tamron SP lenses (A16, A005 and B01) and chose them because I felt their image quality was as good, maybe even better than the comparable Sony or Sigma lenses.
solid build; good fit & finish; very sharp at f/2.8-f/3.1 and tack sharp at f/3.5-f/16; no lateral chromatic aberration; no distortion; IF; quiet af; no front/back focus issues; smooth focus ring; moisture resistant; 6 yr warranty
a-mount connector a bit loose; sharpness declines after f/16; minor bokeh fringing from f/2.8-f/7.1; minor vignetting from f/2.8-f/3.5; lens flair; Sony version lacks VC; AF slower than expected; no case/pouch