Very interesting fact, Akira !
Even the lens diagram is the same with the same position of aspheric lenses...
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Do you think this vario-elmarit is a rebadged Sigma Art ?
I don't think the Leica version is a simply rebadged Sigma Art. The lens barrel and coatings, for example, should be made to Leica's own standard.
The Sigma L mount and the Leica share most probably the same glass. I have the old Sigma/Leica, Akira mentiones and it is not a bad lens. As well some elder R mount Leica wide angels are Minolta lenses and their 28mm shift lens is a Schneider, it is not new for Leica to rebrand other manufacturers lenses. I think they apply in some cases more quality control and they give Leica service on them. No idea how it is in several places in the world, in Germany Sigma service is excellent, so there will be no need to pay double price for a Sigma L mount lens. From what I read in Leica forae the new lens isn´t worse than the Leica zoom, but the real fans say their 90mm is missing for wedding photography. I would be interested to see the difference to the similiar priced Panasonic L lens....has someone here got experience with the new Panasonic line and can explain why they are so expensive?
Oh, you have that Vario-Elmar! When the original 28-70 zoom was made, Sigma was regarded as a you-get-what-you-pay brand. But this particular zoom gained very good reputation in terms of its performance. I would suspect that was one of the reasons for Leica to be interested.
Sigma doesn't exclusively design lenses for themselves. For example, Olympus 75/1.8 for m4/3 is known to be designed by Sigma. Also, I suspect that Panny/Leica Summilux 25/1.4 was also designed by Sigma: the Sigma's own 30/1.4 DC DN Contemporary shares the same optical formula as that of Summilux.
I'm not sure of the reason for the high price of Panny/Leica 24-70/2.8. Because of the licensee cost and Panasonic's own technology like DFD AF, 480fps focus control, etc.?