This could get confusing. First, Sigma announces a 150-600mm f5-6.3 hyper-telephoto, which is great news for sports and wildlife fans because it offers huge reach without the huge price tag of a professional lens. But then it turns out there are two of them.
It's because Sigma splits its lenses into distinct product lines. The 'Contemporary' line is lightweight, portable and practical, the 'Sports' line is big, solid and uncompromising.
And that's the difference between these two lenses. On paper, the look the same. Both offer a 150-600mm zoom range, both have an aperture range of f5-6.3, and both feature Sigma's OS optical stabilization system.
Physically, though, they're quite different.
The Contemporary version measures 260mm long by 105mm across. The Sports version is much bigger, at 290mm long and 121mm across. Sigma doesn't quote a weight for the C lens, but the S version is a hefty 2.86kg.
They're quite different inside, too. The C lens has 20 lens elements in 14 groups, while the higher-specified S lens has 24 elements in 16 groups. Clearly the Sports lens is designed for higher-grade performance, but the Contemporary version will be much easier to use handheld.
The S version will go on sale in September at a price of £1,600, with details about the Contemporary version to follow.