Tokina 11-20mm Focus Problems BMP 6K

Hi to all

I got a BMP 6k EF and try to use a Tokina 11-20mm lens.

After changing the PL mount to an EF mount, I can not find the right Focus, even with different numbers of shims.

The infinity on 20mm is marked at 0,7m!
With the max. of shims its about 1.0m!

Any ideas?

Thanks Patrick

Ps. The EF mount is the original from Tokina

B&H has the following note for this lens:

Lens mounts may be changed by the user but mounting by a lens service center is recommended to ensure accurate focus scales.

Well let me say, it's not my first lens that I change Backfocus via shimrings but its seems to be the first lens, which does not match at all.
Usual the shimrings are just for small corrections of the focus. But with or without it's miles away from a acceptable result

It was my understanding that you are an experienced user. It just seems that with this Tokina lens there is more to it than just shimming.

Maybe this will help

Can I just ask, having 0 experience with still lenses in my life, what is the rationale behind a zoom lens with less than 2:1 ratio, for filmwork? I imagine in stills it offers you some compositional refinement, for shots but surely in cine work, backfocus/parfocal precision hardly matters with such a range?

Steve, the difference between 11 and 20mm is huge.