Sat Nov 10, 2018 5:51 pm
With the BMPCC4K connected to AC power using the supplied adapter, I get iris fluctuations / focus shifts while moving the Olympus 12-40mm zoom ring.
When using battery power, or a battery coupler, the issue doesn't occur at all.
Can anyone else with this lens confirm?
Example: https://vimeo.com/300061794/be6acf55eb
UPDATE: After more testing this only seems to happen with skin contact, i.e, if I control the zoom ring with a rubber gear belt the problem goes away. Weirder still, only if I grip the ring top and bottom, forefinger at the top, thumb underneath, etc. Clearly this is a grounding issue.
I'm now trying to ascertain if this problem is with the camera or lens.
When using battery power, or a battery coupler, the issue doesn't occur at all.
Can anyone else with this lens confirm?
Example: https://vimeo.com/300061794/be6acf55eb
UPDATE: After more testing this only seems to happen with skin contact, i.e, if I control the zoom ring with a rubber gear belt the problem goes away. Weirder still, only if I grip the ring top and bottom, forefinger at the top, thumb underneath, etc. Clearly this is a grounding issue.
I'm now trying to ascertain if this problem is with the camera or lens.
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