Stereoscopic view question

[atamasan]

Hello.
I have a question. When I use HMD, I know I must use viz.go(viz.HMD).
I can see 3D objects through the HMD. And I know the "ipd" should be set because the value is different each person. So I changed the value to see the effect of ipd. I changed like this:
viz.ipd(.2)

But nothing changed. So, after that I tried again, like this.
viz.go(viz.STEREO|viz.HMD)
viz.ipd(.2)

This time(when I use viz.go(viz.STEREO|viz.HMD)), objects were rendered only right side of the window. What are the reasons for this? Please let me know.

PS I am using emagin's z800.

Thank you .