Mike Hoppa read the Zeiss Loxia 21mm f/2.8 lens review at Photochirp and the author wrote: “nice thing about these lenses, and mirrorless lenses in general, is that they can be designed differently (often smaller) to DSLR lenses”, he wanted to know if it is true, so he asked Zeiss if lenses for mirrorles can be smaller than dslr, and here is the official Zeiss answer:
We have an answer for you now: because of the shorter flange focal distance of mirrorless camera systems compared to SLR systems (e.g. E-mount: 18mm, F-mount: 46.5mm), some lenses could be designed differently. This could result either in a slightly smaller (shorter) barrel, or in a more complex, higher performing lens compared to a comparable SLR lens of the same focal length and speed. Of course, it is not possible to overcome the laws of physics. The diameter of the entrance pupil is always fixed by the focal length and speed.
Completely new optical designs like our Loxia Distagon T* 2,8/21 benefit from the short flange focal distance of the E-mount, leading to a more compact lens compared to the SLR lens with the same data.
ZEISS Camera Lenses Team
So, thanks to the shorter flange focal distance of mirrorless camera systems, the E-mount mirrorless lenses can be slightly smaller (shorter) and lighter than the DSLR lenses.
Store links to all Zeiss Batis and Loxia lenses:
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