In the past few years, Sigma has mostly focused on standard focal lengths between about 20mm and 135mm, but that does not mean they do not have their eyes on more extreme options. In fact, three new patents have emerged for lenses with long focal lengths ranging from 400mm to 700mm.
The three patents are for 400mm f/5 OS, 500mm f/5.6 OS, 700mm f/8 OS lenses. Though Sigma mostly focuses on more conventional focal lengths, the company does have experience with longer focal lengths, both prime and zoom, including lenses like the 500mm f/4 DG OS HSM Sports and 150-600mm f/5-6.3 DG DN OS Sports, along with more extreme options like the 300–800mm f/5.6 EX DG HSM, affectionately known as the "Sigmonster," and the 200-500mm f/2.8 EX DG, the only lens that offers the combination of a 500mm focal length and f/2.8 aperture.
That being said, just because a lens is patented does not mean it will actually make it to the market. Nonetheless, the last couple of years have seen a surge in popularity of supertelephoto lenses with relatively narrow apertures, as they enable photographers to explore focal lengths that were previously inaccessible due to high prices, while the improved ISO and autofocus performance of modern cameras keep those apertures from being as much of an issue as they might have been years ago.
Let's go Sigma! Z-mount models please.
I sure hope that Sigma is allowed to make these new lenses in Canon's RF mount.
I currently use Sigma telephoto zooms because Canon refuses to make anything like them. The Sigma 300-800mm f5.6 and the Sigma 60-600mm f6.3 are my most-used lenses. Would absolutely LOVE Canon versions of these lenses, but Canon doesn't seem to make anything very innovative or different when it comes to supertelephoto zoom ranges.
The proposed 700mm f8 is of real interest to me, and I am almost certain that I would buy one if they actually go ahead and make it in a mount that I can use.
I would really like to see these Sigma patents include a built-in 1.4 teleconverter for these three lenses. That would drastically increase their usefulness while only moderately increasing their cost, size, and weight. 80% more useful, but only 30% more expensive and 15% bigger & heavier ...... sounds like a no-brainer to me!
I have the Sigma 300-800 f5.6 zoom. Love it for photographing our urban falcons. But it weighs about 13 pounds and the focusing is slow by today's standards. I'd love to see an updated version that cut a few pounds off and had faster focusing.
I also have the Sigmonster. Recently I added a Sigma 60-600mm, and I use it a lot more than I use the Sigmonster now.
Sigma, if you make Z mount tele I am sure you will make a lot of money. In addition, many of us will be very happy.