Archived posting to the Leica Users Group, 2012/11/30
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]That is very true about the cost being higher on Leica lenses, however the cost of new AF lenses from Canon and Nikon are not exactly cheap either, so yes I expect them to be correct at purchase. and yes i understand that there is some error in digital loop designs, designed many over my day, and we were expected to keep the design very tight at my employer, but when the lens Af is off by a noticeable amount, that is not acceptable. Gene ----- Original Message ----- From: "Frank Filippone" <red735i at verizon.net> To: "Leica Users Group" <lug at leica-users.org> Sent: Friday, November 30, 2012 3:28:52 PM GMT -06:00 US/Canada Central Subject: Re: [Leica] Leitaxed R lenses on Nikon Well, in M terms, if I paid 10 ( 50 Summilux ASPH) to 50 ( 50 ASPH Summicron) times the cost of a N or C standard lens, no less something exotic, I too would expect the lens came with repeated FREE calibrations. ... because they ARE closed loop AF lenses. Errors are taken out in the AF control loops. AF does not mean no errors, it means closing the loop in focus around some artificial zero. The artificial zero is not absolute zero. It has offset and gain errors. The specific lens and he specific body are then nulled against their combined errors, in the adjustment SW in the camera. It is a really good system ( in theory). NASA uses it every day. I did a LOT of servo design and implementation and debug. Frank Filippone Red735i at verizon.net If Leica did this with their S2 lenses, think of the outrage that would generate from the users. They would be returning the lenses and demanding a repair or their money back. Maybe the N or C users just don't expect the lenses to be right on, in this day and age of the Software can fix it photography. I also hear that you must use the Sharpen function on all digital images to get them sharp, when I tell them I do not need to do this with my Leica digital images they are amazed. Cheers, Gene _______________________________________________ Leica Users Group. See http://leica-users.org/mailman/listinfo/lug for more information