Autofocus noise reducer VideoZizzle a hoax?

17 Sep

As with many new technologies, it seems that Piezo-electric autofocus motors (silent, lens drives elements) are currently more prone to failure than passive lenses that accept the camera’s screwdrive motor. So much so that there seems to be an expectation that those lenses will jam or otherwise die eventually and require repair. This assumption does not seem to accompany screwdrive lenses, where it seems users would be surprised at failure rather than expecting it. There are two reasons why many still prefer Piezo-driven lenses: One is that they are virtually silent, the other is that they are often faster

One area where the noise emitted by screwdrive lenses is particularly bothersome is in videography. But help is at hand, apparently, as a new algorithm can filter out the noise made by autofocus or zoom motors. It seems that this is possible only in firmware because the firmware would be able to know when those motors were engaged and hence filter only at those times. That suggests that other sounds recorded at those times would be affected by the filtering, and therefore speech, for instance, would sound distorted in the final product due to the AF noises filtered out. This is confirmed both by Petapixel silently retracting an earlier comment that said the technology would also be able to filter out noises made by image stabilisation systems, and by two demo videos published by the VideoZizzle team that use a hardly audible zoom motor to demonstrate (very unconvincingly) that music or speech would not be distorted.

Additionally, I have unanswered questions about how these demo videos were produced. I have to assume that the correction was made in PP, with a separate track in the RAW file keeping record of whether AF/zoom were engaged or not. However, half of me suspects that the voices and music were added after the fact, and the demonstration is therefore misleading and not a real demonstration.

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