Photographyblog posted the full Zeiss Batis 40mm FE lens review:
The Zeiss Batis 40mm f/2 is an outstanding short-standard prime lens. The novel 40mm focal length takes a little while to get used to, falling as it does between the more “normal” 35mm and 50mm focal lengths, but it quickly loses any real significance after you’ve used it for a while.
Sharpness is very high across the frame. Even with our A7R II test camera recording 42-megapixel images, detail is exceptionally sharp. Shooting at the maximum f/2 aperture does reveal a minor reduction in sharpness, but this is already resolved by f/2.8, and even at this aperture the lens is able to produce beautifully smooth bokeh.
Some vignetting is apparent when shooting wide-open at f/2, but quickly disappears as you stop down, while chromatic aberrations, distortion and flare are all very well controlled, and the bokeh is very appealing for this type of lens. The 24cm minimum focusing distance and 1:3.3 magnification ratio makes the lens versatile enough to shoot close subjects.
The Zeiss Batis 40mm f/2 proved to be a pleasure to use, thanks to its superb build quality, smooth focusing ring and innovative OLED display. When manually focusing, together with the A7R II’s excellent Peaking feature, the Zeiss Batis 40mm f/2 delivered a very high percentage of keepers, and it also proved to be very quick, quiet and accurate when auto-focusing.
There’s only one real drawback to the Zeiss Batis 40mm f/2 lens – the asking price. £1129.99 / $1299.99 / €1,299 is a lot of money to pay for a standard prime lens, even one as well featured and built as this.