the macro term is loosely applied, in general in means some sort of close focussing, ususally 1:5 magnification or greater. To me a "real" macro lens is always a flat field prime optimized for closeup, with at least 1:2 mag- nification or greater.
----------------- J.C.O'Connell [email protected] ----------------- -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Igor Roshchin Sent: Friday, June 15, 2012 2:10 PM To: [email protected] Subject: What does the "macro" mean? ... Well, I understand the meaning of the word. But what does it actually mean in the lens designation? The new Sigma 18-250 lens is called "macro" "with a maximum magnification ratio of 1:2.9": http://www.dpreview.com/news/2012/06/15/Sigma-launches-18-200mm-F3-5-6-3-Mac ro-HSM-superzoom-lens One of my older version Tamron zooms (70-300/4-5.6) and Sigma 24mm /1.8 EX DG are also marked as "Macro". While Sigma 24/1.8 goes to short focusing distances (about 18 cm / 0.6 ft), Tamron - doesn't (the shortest focusing distance is about 50 or 70 cm). In contrast, D FA 100/2.8 Macro - has a clear long tail of focusing distances where you achieve the macro regime. So, what is necessary and sufficient for a lens to be called macro? Igor -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
