The non-weather-sealed version of the lens is imminent.
The third-party lensmaker's new supertelephoto won't cost much more than an earlier 200-500mm model with no image stabilization.
When it ships, the new lens will offer long-range sports and wildlife shooters some new competition, but it's not as fast a supertele as some rivals.
The M.Zuiko 300mm f4 IS Pro is an excellent pro supertelephoto lens for the Micro Four Thirds mount.
Not to be left behind in the supertelephoto zoom department, Sigma literally one-ups one of its main rivals with the announcement of two different 150-600mm zoom designs.
A built-in 1.4x extender pushes Canon's forthcoming 200-400mm zoom to a maximum of 560mm. Also: higher prices but lower weights for new 500mm and 600mm supertelephotos.
The Japanese SLR powerhouse plans to endow its 300mm and 400mm telephotos with preset points with motorized focusing. Also: expect lighter 500mm and 600mm superteles.