With meaningful ergonomic and user interface improvements, the a9 is a polished and highly capable camera. It may not be a go-to camera for landscape and studio photographers, but its compact dimensions, silent operation, abundant speed and blackout-free shooting make it not only a step forward for mirrorless, but a compelling proposition for professionals who can't afford to miss a moment.
The Digital Picture
The a9 takes Sony's camera lineup to a new level of performance, including a 20 fps frame rate, silent shutter and no-blackout viewfinder. The ease of use improvements found should similarly be considered. This very capable camera's biggest shortcoming, at least for some professional photography pursuits, is the lack of wide aperture, long focal length lenses, to be erased in the near future.
The Sony A9 is a landmark camera. It shoots faster and more autonomously than any other camera. Set it as you want it, and it will self-focus and shoot anything in any light with ease — so long as you use good lenses. Much of the fast focus magic is lost if you waste time with old lenses not optimized for Sony mirrorless cameras.