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Weird behavior - quick refocus when zooming DA*16-50/2.8 PLM on K-3 III

Started 4 months ago | Discussions thread
Kobie M-C
Kobie M-C Contributing Member • Posts: 701
Re: Weird behavior - quick refocus when zooming DA*16-50/2.8 PLM on K-3 III
1

MarBa wrote:

Hi everyone,

I noticed that sometimes when zooming with the DA*16-50 lens, the K-3 III camera would activate AF (red light turns ON for a short moment) and refocus the lens quickly back and forth (very obvious in the OVF!). This happens always at the same focal length when zooming in or out .. but it does not seem to be always the exact same focal length on different occasions (not 100% sure about that). Interestingly, the "MF" symbol also appears in the viewfinder at the same time when AF is activated. I tried to clean contacts on the lens and the camera but it still happens. But often .. a bit later in the day .. it just stops doing that ... so it's weird, not perfectly reproducible.

Anyone noticed something like that? With this combination, or other lenses/cameras?

Best,

M

I've noticed it on my 55-300 PLM on occasion when zooming. It'll re-focus on its own. Not all the time though. I haven't noticed in the 16-50 PLM. I use the lenses differently though (I don't zoom after focus with the 16-50). I'm guessing that it's something with PLM behavior.

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