Standard product images for the Sigma 180mm f/2.8 EX DG OS HSM Macro Lens have been added to the comparison tool.
The link will show the big Sigma 180mm f/2.8 EX DG OS HSM Macro Lens beside the medium-sized Sigma 150mm f/2.8 EX DG OS HSM Macro Lens and the smaller Sigma 105mm f/2.8 EX DG OS HSM Macro Lens.
The Sigma 180mm f/2.8 EX DG OS HSM Macro Lens review page has addition on-camera product images.