http://news.mapcamera.com/KASYAPA.php?itemid=25933

Lens delivers outstanding sharpness in the centre of the frame almost throughout its aperture and zoom range, and also performs very well at the edges of the frame too.

http://www.photographyblog.com/reviews/sony_vario_tessar_t_fe_16_35mm_f4_za_oss_review/

The lens performs admirably and with it being an f4 constant aperture offering, we barely ever found a big reason to want to stop it down. This lens is designed for the photographer that loves to shoot wide. Whether its for landscapes, products, real estate, events, or creative portraits–this lens is highly capable due to its super wide angle to semi-wide angle at 35mm.

http://www.thephoblographer.com/2014/12/20/review-sony-zeiss-16-35mm-f4-oss-sony-full-frame-e-mount/

Subjective assessments of test shots showed the review lens to be a good performer, delivering good centre-of-field sharpness, well-resolved detail and accurate colour rendition. Quite a lot of corner softening was found at the shorter focal lengths, probably caused by curvature of field, which is not uncommon in ultra-wide-angle lenses. Stopping down largely eliminated it.

http://www.photoreview.com.au/reviews/lenses/other-ilc/sony-vario-tessar-t%2A-fe-16-35mm-f-4-za-oss-sel1635z

It delivers good performance in terms of sharpness and distortion and is almost free of artefacts such as vignetting and chromatic aberration. Its resistance to flare is quite impressive. This should be enough to consider this lens for landscape photography. For architecture, it can work well but you might notice some more distortion or lack in sharpness at the corners.

http://www.mirrorlessons.com/2015/04/09/sony-fe-16-35mm-f4-review/