pixels jitter in Z pass

[rleuchovius]

Hi

I have a question regarding an issue I have stumbled upon. It has suddenly started appearing, haven't experience this before.

The Z pass revelas pixels at random positions that are hopping around in the frame. (I have to put on an exposure with a value of around -13 to see the z correctly.)

These pixels make it impossible to use the pass as a fog layer or dof layer since it has artefacts.

Can anyone give me an explanation for this?

See the attached image

[rleuchovius]

Here is a lowres mov file also. If you zoom into it you can see black pixel dancing around.