# Patent: Sigma 12mm f/2.8 optical formula



## Canon Rumors Guy (Dec 1, 2018)

> It looks like Sigma is continuing to work on wide angle lenses for full frame cameras. A recent patent application shows an optical formula for a 12mm f/2.8 Art series lens for full frame cameras.
> 
> 
> *Sigma 12mm f/2.8 Art Specifications:*
> ...



Continue reading...


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## mb66energy (Dec 2, 2018)

Interesting triple use lens: very wide for FF, wide for APS-C and - if I find time and motivation - a good candidate for a (3D-printed) shift adapter made of a EF->EF-M adapter and a shiftable interconnect. But I need a tripod mount for the lens!
... quadruple use lens: compatible with small filters via RF filter adapter !


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## helpful (Dec 3, 2018)

I would love a 12mm f/2.8 prime lens, except I have the feeling that lenses, especially wide-angle lenses, for the current EF mount will go obsolete more quickly than usual in favor of lenses for the RF mount.

The RF mount, with its 20mm flange focal distance, versus 44mm for the EF mount, enables optical designs which are of equal or better optical quality while using less super-expensive optical glass. Less glass means that the lenses are not only smaller and easier to use, but also means that the lenses can allow customers to save money and/or Canon to make a bit more profit and thereby invest that added profit in developing new technology faster and better for all of us to benefit.

The RF mount is the future, a very, very bright and promising future. I am especially happy Canon chose to go with 20mm to maximize the strength of the mount while still achieving an optically-optimized mount solution compared to which the previous EF mount was at a 220% disadvantage (44/20).

This is a huge deal, as attested to in spades by the incredible optical quality of new RF lenses like the f/1.2 50mm and f/2 zoom. Those lenses would have been unmanageably huge and nightmares of optical complexity just to achieve equivalent image quality when engineered with a 44mm flange focal distance in mind.


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## Stuart (Dec 3, 2018)

So would / could sigma do an RF mount for this?


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## Antono Refa (Dec 3, 2018)

I'm not sure what would be the point of such a lens.

The Laowa Zero-D 12mm f/2.8 would be a direct competitor, and the EF 11-24mm f/4L and Sigma 12-24mm F4 DG HSM Art as alternatives as well.


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## Pooshoes (Dec 4, 2018)

Antono Refa said:


> I'm not sure what would be the point of such a lens.
> 
> The Laowa Zero-D 12mm f/2.8 would be a direct competitor, and the EF 11-24mm f/4L and Sigma 12-24mm F4 DG HSM Art as alternatives as well.



I use the Laowa as a real estate Workhorse. It is a great lens and I don't see how the sigma could improve unless it has auto focus.. I use this lens on my EOS are with the adapter and it is flawless I love the focus peaking


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## [email protected] (Dec 4, 2018)

Not to be gripy, but there are many more supertelephoto spots to fill


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## hamoser (Dec 4, 2018)

Sigma seems happy to reuse their extra special front element as much as possible. I'd still be interested in this lens though.


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## Antono Refa (Dec 4, 2018)

Pooshoes said:


> I use the Laowa as a real estate Workhorse. It is a great lens and I don't see how the sigma could improve unless it has auto focus.. I use this lens on my EOS are with the adapter and it is flawless I love the focus peaking



Auto focus isn't all that useful on such a wide lens.


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## hamoser (Dec 5, 2018)

Antono Refa said:


> Auto focus isn't all that useful on such a wide lens.


Does Sigma even make MF lenses?


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