I have seen many threads about these lenses being loud. On every one there is always one or more guys who claim their copy is silent. I have been through two copies now and both show similar noises and neither would I consider anything close to silent. So either all these people with silent copies are partially deaf, or Zeiss quality control is really bad.
In comparison, my Sony 24-105 f4 exhibits no such noises when subjected to the same test.
So please tell me, how do I determine if my copies are normal?
And if they are both normal, why does Sony put out a lens that is so loud that it cannot function in video mode without leaving audible noises behind?
Video begins at f22, makes passes with both AF-C and manually pressing the AF button, then switches to f1.8 and repeats the process. The noise is present at both apertures. (If you can't hear it you probably need headphones or better speakers.) Sorry for the background noise, this was the quietest place I could find that maximizes the noise.
Here is a better real world example, shot in better light. The whole thing is at 1.8. You can still clearly hear the lens focusing after each pan.