Awesome lens, very sharp at all focal lengths, fast and accurate AF, OSS works great, highly recommended lens for wildlife!

Very sharp image quality. I have been using it with the a6500 for wildlife and comparing it to my old setup of a Nikon D500 with the 200-500mm. It seems just as sharp. This lens is much quieter than the Nikkor. The size and weight is nice for hiking. The lens has an amazingly close minimal focus distance and is surprisingly good for shooting insects. I like the removable foot which makes packing it into a tight camera backpack easy. If Sony is smart they will produce some quick release accessories for this such as the eyes for your shoulder strap or an ARCA Swiss plate. It is a lens done right, and I have to thank Sony for all the obvious thought that must have gone into it.

I use this on the A9 and the A7rII. On the A7RII the focus hunts alittle and is not as fast as when mounted on the A9. But that is the camera bodies and not the lens. I have been using the Canon 400mm 5.6 on both of these bodies. The Sony lens, at 400mm, is as sharp and possibly sharper then the Canon lens and the Canon is one hell of a sharp lens. This is a fine lens and can be used effectively on either of these Sony bodies.

Another high quality lens from Sony. Snapping on the FE 2x to shoot the Eclipse next week! I used this on my A9 and my Sony FS100 Video Cam with excellent results. Glad I left Nikon!

After having this lens for a few weeks, I am impressed. I had the A-mount 70-400 mm (and also still have the Minolta APO 400 mm f:4.5), and the E-mount lens is better than it's A-mount zoom sibling in every respect. This lens even focuses fast with my old A7 camera, and can successfully be used for action, like birds in flight. I also like how the tripod socket foot can be removed from the lens, very clever design. Sharpness and contast is excellent wide open at 400 mm, which is the main reason I bought this lens.

This lens is great for wildlife. It is fast focusing and very sharp.

I bought this wonderful lens a week ago. It focuses quickly on the Sony A7R. So far, I have used it to photograph a swallowtail butterfly. I shot handheld at 400 mm, f/11 aperture preferred, and the camera set the shutter speed over 1/1000 sec. The attached photos are edited and cropped. It is a delightful lens to use.
The lens uses a lot of power, so I bought a vertical grip and another battery (now 4 total).

A6500 & FE100-400 - fast focus and very sharp all the way from 100 to 400! Test included hand held, Opteka shoulder mount, monopod & tripod. The lens has many features that make it easy to use!

Just received this lens and spent several hours testing it. First I shot many images of my bookcase at various focal lengths with my a7rII to see the I got a good copy of the lens. I checked every corner very carefully. I mostly shot all the tests at f11 because I am a landscape photographer and this is the f stop I normally use. Everything looked great. So far I'm keeping the lens. Next I took the lens outside and tried it at all focal lengths to see how it did in the real world. I was not disappointed. In fact, I'm supper pleased with the sharpness of this lens. I have been a professional landscape photographer for over 30 years, and have owned the best lenses out there up to 600mm. In terms of sharpness, this rivals any lens I have ever used. I also used it with the 1.4x teleconverter, and really could see no degradation even at 560mm. I normally don't use auto focus, but I was also pleased at how fast it focused even with the 1.4x converter. Now if I were a serious animal/bird photographer I would probably need a faster lens, but for my travel/landscape images this is a perfect lens.

I use this lens for my wildlife photography. The lens on my A7rii is fast and very sharp. I recently ordered the 1.4x to going along with this combo. I let some friends test the lens out on their A6300 and they pre ordered the next day.