Viltrox EF-EOS M2 and F1.2 lenses focus issue

I just received the Viltrox adapter and immediately tested it with a few of my lenses on the M50.
On my 50f1.2 and 85f1.2 focus continuously hunts back and forth and never locks.
It works on the 35f1.4 and reports as f1.0. It works with the Tamron 24-70 f2.8 as well.

I don’t know if it’s my copy but anyone else has the same issue with f1.2 lenses?

A couple of pics of the 35 f1.0

You may be interested in this thread -> https://photography-on-the.net …/showthread.php​?t=1508269 unless this is the speedbooster adapter and not the EF adapter, then you won't care about that thread.

The M2 is the speedbooster, I believe. However you say the shots are from the 35 1.4, but EXIF shows up as 50mm f1.2. Something seems amiss.

I have had no issues with hunting using my Sigma 50 1.4 and .71x booster, but don't have any EF lenses faster than that.

Thanks. Yeah this is the booster Viltrox I read that thread and turned off continuous AF before I got the adapter haha.
No the 35 f1.4 doesn’t turn into the 50 f1.2 but it turned the available aperture to 1.0 from the camera. This lens works great with the adapter.

The 50/1.2 and 85/1.2 couldn’t focus at all with the adapter. I even updated the firmware to 2.14 and 2.13.

Do you have a f1.2 to quickly test?

sonnyc wrote in post #18891944
Thanks. Yeah this is the booster Viltrox I read that thread and turned off continuous AF before I got the adapter haha.
No the 35 f1.4 doesn’t turn into the 50 f1.2 but it turned the available aperture to 1.0 from the camera. This lens works great with the adapter.

The 50/1.2 and 85/1.2 couldn’t focus at all with the adapter. I even updated the firmware to 2.14 and 2.13.

Do you have a f1.2 to quickly test?

Unfortunately no, the only f1.2 I have is a 50mm native to the M mount.

UPDATE: After talking to Viltrox they confirmed that it doesn't work with the 50 and 85 f1.2.
I ended up return it.