http://www.dpreview.com/articles/24...have-survived-because-we-make-unique-products Sxns related to mirrorless lenses: Sigma creates lenses for DSLR and mirrorless systems now - is mirrorless an important segment for you now? Not yet. According to industry data, camera to lens ratio [attachment rate] is still something like 1:1.3 in the case of mirrorless cameras, and 1:1.7 for DSLRs. So conventional DSLR users buy more lenses. Mirrorless camera users are more likely to purchase the camera with a kit lens and not many people purchase any additional lenses. Some high-end mirrorless users with Sony NEX-7 or Olympus OM-D buy more but the majority of mirrorless users are the entry-class users. Our main target is a bit higher. Are you interested in creating lenses for Sony’s new Alpha 7 and 7R? As a major lens manufacturer we believe it’s our mission to support as many systems as possible but we have limited resources so we have to prioritize. But we’d like to. How much do you talk to camera manufacturers like Sony, Canon and Nikon in your day-to-day business? Not at all. Of course I have friends in other companies who I talk to frequently but we don’t discuss business. From a technical point of view is it easier or more difficult to make lenses for mirrorless cameras versus DSLRs? There is no difference in terms of difficulty per se, but mirrorless and DSLR are different. In terms of mirrorless lenses, the cameras use sensor-based autofocus, and also support movie recording with full-time AF which means that the focusing element must be small and lightweight. So if we needed to make a very fast, large-aperture lens for mirrorless, that might be more difficult than for DSLR. But generally speaking, although the design approach is different there’s no real difference in difficulty. You mention video - how much does the need for video influence your decision-making now, when you’re designing new lenses? In the case of DSLRs. we haven’t changed the way we design. Because autofocus is still performed using phase-detection so we use the same design approach. For video with DSLRs I think most users focus manually. For mirrorless we have to support full-time autofocus as I’ve said so we must design the lenses differently, with smaller and lighter focusing elements.