Why I am getting different values for depth of field from calculators vs in-camera DoF preview?

When using depth of field and hyperfocal calculators, I get very different result versus the in-camera DoF preview of my Fujifilm X-M1.

For example:

With DOFMaster (or any other online calculator), for a Fujifilm X-M1, with a focal length of 16mm and f-stop = 8, I am supposed to get hyperfocal distance at 1.62 meters with DoF from 0.81 meters to infinity.

If I use those settings on the camera, in-camera DoF preview shows that DoF is about from 1.2 to 2.5 meters.

What am I missing?