The Sigma is so weak at the long end that (in the sample I had) images appeared out of focus.
People usually recommend Tamron's version of the same telezoom. But both will be outperformed by Pentax's forthcoming DA 55-300 and DA* 60-250 F4. The SMC F 70-210 is quite good, but I haven't tried it on the K20D's sensor. Joe -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
