Jack Dallas
This is a sharp and stable lens. The IS (image stabilization) is especially impressive. I got a few sharp hand held images at 300mm shot at 1/25th sec. with a higher success rate by 1/80th sec. [Photo of squirrel was 1/80 sec. @ 300mm] This far exceeds the recommended 1/300th sec. for this focal length on a full frame camera. As others have mentioned, this is not an "L" caliber lens from Canon ($1350.00) but a less expensive zoom with a more manageable weight. The new LCD information window is not useful to me as focal length is already printed less than an inch away on the lens body and depth of field may be better determined with the "preview" button or by looking at a test shot. I have not tested the focal responsiveness of the new nano focus feature but I will assume it is on a par with my 18-135 lens with the same engineering. Nano focus is used for continual fast auto focus, especially while shooting video. For stills, the auto focus is fast and responsive. My tests so far have been on my full frame Canon 5D Mk IV and even the corners appear sharp. See the red hibiscus image where the yellow stamin in the corner is sharp. My 300mm f4 L series prime lens is slightly sharper with more contrast but it weighs more, cant zoom and costs significantly more. This zoom is a fine vacation lens where the weight reduction is greatly appreciated. The IS (rated at 4 stops) means the loss of light from a 5.6 lens can be somewhat compensated with a slower shutter speed (with a stable subject). The lens bokeh (out of focus background blur) is pleasant and useful to isolate the subject (see the image of the dove). All of the attached sample images were hand held. I will further test the lens on a crop sensor Canon 80D and will report any changes here. On a crop sensor camera, this lens becomes a 112mm to 480mm zoom.
