To view full test results and scores for the Pentax 645D click here;
for the Sigma 70-200mm f/2.8 EX DG OS HSM Canon click here;
for the Sigma 17-50mm f/2.8 EX DC OS HSM Canon click here.
Further readings for the New data on DxOMark for Pentax 645D, Sigma 70-200mm f/2.8 EX DG OS HSM Canon and Sigma 17-50mm f/2.8 EX DC OS HSM Canon
To provide photographers with a broader perspective about mobiles, lenses and cameras, here are links to articles, reviews, and analyses of photographic equipment produced by DxOMark, renown websites, magazines or blogs.