According to Sony it was their first E-mount medium telephoto macro lens with built-in image stabilisation delivering outstanding G Lens quality: stunning resolution at up to 1:1 magnification plus gorgeous background bokeh when required, even when shooting handheld [I always shoot handheld]. A floating focus mechanism ensures that consistently superior optical performance is achieved at all focusing distances.
I purchased the lens many years ago on the day it became available [it was launched in June 2017 and even though I immediately pre-order it did not arrive until year end] and it was in fact my first G or GM lens and at the time I was a bit shocked by the price [it now sells at Euro 1399] but I had just been paid by a US publication for a number of photographs so I had the cash. I collected it from Conns Cameras on Christmas Eve but when I tried to use it on Christmas Day it would not focus but I had no problem having it replaced.
The lens features a weather resistant plastic exterior with a matte black finish. The lens is currently the only Sony E-mount lens to feature an external focusing ring, which can be pulled up or down relative to the lens body to switch quickly between manual and autofocus. On the side of the lens are a pair of external switches controlling the lens' focusing range and image stabilisation.
The lens' autofocus motor is fast and accurate on all Sony E-mount cameras, with only mild hunting when shooting at its closest focusing distance in low-light situations.
The lens has exceptional sharpness straight from its maximum aperture of f/2.8, with very little chromatic aberration, distortion, and vignetting.
REVIEW:
https://www.kenrockwell.com/sony/lenses/90mm-f28.htmREVIEW:
https://www.ephotozine.com/article/sony-fe-90mm-f-2-8-macro-g-oss-lens-review-29635