Zeiss Batis 135mm f/2.8 review: Focusing
The lens autofocuses accurately regardless of where the focus point is placed in the frame. Sony Alpha 7 II, 1/1600sec at f/2.8, ISO1600
When it comes to autofocus, the Batis is extremely well-behaved. I’d never expect this kind of fast prime to offer super-fast autofocus, but it’s pretty quick under all but the lowest light conditions. It’s also essentially silent, making it both unobtrusive for stills shooting, and an attractive option for videographers who wish to pull focus from one subject to another during recording. Most importantly, though, it’s consistently accurate, no matter where in the frame you place the focus point: this is a huge advantage of the on-sensor autofocus systems used in mirrorless cameras. But with such narrow depth of field you need to pay very close attention to where you place the AF point, and ideally use the finest focus area possible, to guarantee the most accurate results. One thing you’ll quickly notice when shooting people is that the slightest movement of your subject can throw your focus fractionally out when viewing images at the pixel level onscreen.
Choosing a small AF area helps prevent the camera getting confused by layered scenes. Sony Alpha 7 II, 1/800sec at f/2.8, ISO800
Manual focus is electronically, rather than manually controlled, but still does a pretty good job of mimicking the feel of a traditional manual focus lens. The focus ring rotates extremely smoothly, although with no hard end-stops to mark the limits of the focus range. Again the Alpha 7’s electronic viewing makes it especially easy to judge accurate focus, not only because the viewfinder gives a completely accurate depiction of focus and depth of field, but also because of the focus aids available, including peaking and magnified view displays.
