<p>I am looking at extending my lens set to super-wide. The Voigtlander 15mm lens made by Cosina looks like an interesting option (and far cheaper than Leica-made glass), and the importer describes it as a rectilinear lens, i.e. not fish-eye in its perspective. Would like to know what experience other Leica shooters have with this and other Voigtlander lenses and how you appraise their optical qualities (sharpness, contrast, color). </p>