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New lens data sheets and max aperture


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When you look at http://us.leica-camera.com/content/download/120636/1219177/version/9/file/Technical-Data-Leica-APO-Vario-Elmar-T+55-135+ASPH._EN.pdf and http://us.leica-camera.com/content/download/120633/1219138/version/9/file/Technical-Data-Leica-Super-Vario-Elmar-T+11-23+ASPH._EN.pdf

 

They have MTF charts for what I would expect are impossible focal distance and aperture combinations. For example, I would expect 55mm and f/3.5 but it is surprising that they have 85mm and 135mm f/3.5 MTF chart. To me this would indicate a 55-135mm constant aperture f/3.5 rather than a f/3.5-4.5. A similar thing is true for the 11-23mm lens.

 

Doing the math a 135 at f/4.5 is 30mm while a f/3.5 is 38.5mm. With a lens barrel diameter of 68mm, a 38.5mm aperture doesn't sound mechanically impossible. 23mm at f/4.5 is 5.1mm while f/3.5 is 6.6mm.

 

The 18-56mm's data sheet collection of MTF charts does match the lens's maximum aperture.

 

Is this likely an error on Leica's part or is it more likely that the lens will have a wider aperture when zoomed in than originally announced? If it was just one number, I would totally assume it was just an error but the fact that it is a whole graph different than other graphs and hopefully backed by measurements makes me curious.

 

Has anyone seen these lenses yet?

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