Samyang 24mm T/1.5 cine lens for Sony E-mount, about $699 at B&H Photo.
The Samyang 24mm T/1.5 (f/1.4) offers a full-frame wide angle view for the Sony A7/A7R (the Sony Zeiss 24mm f/1.8 Sonnar covers only the APS-C frame for NEX cameras, not full frame).
The appeal of the Samyang as a native-mount lens is clear no adapter needed. But it is a manual focus lens with fully manual aperture control—perfect for some types of shooting, inconvenient for others. In fact, the lens is not chipped at all—the camera does not know which lens, which aperture, etc; no EXIF data is communicated. Which is of course the same as mounting any lens via lens adapter.
As a DSLR lens with a telecentric design, it does not have any ray angle issues.
In Guide to Mirrorless are two new aperture series with the Samyang 24mm T/1.5. HD and UltraHD crops images and large crops explore the performance, which might be enticing for some.
Aperture Series: Creek Entering Pool (Sony A7 + Samyang 24mm T/1.5)
Aperture Series: Still Pool Above Creek (Sony A7 + Samyang 24mm T/1.5)
Creek Entering PoolSony A7 + Samyang 24mm T/1.5
Still Pool Above CreekSony A7 + Samyang 24mm T/1.5
Samyang 24mm T/1.5 (cine version)
for Sony A7/A7R