Forum Discussion
Rift latency
Has anyone else measured the Rift's end-to-end latency? By this I mean movement time to photons off the screen time. I am getting numbers around 25-35ms measured using the official Unity plugin. Can a...
"geekmaster" wrote:
... depending on what scanline you begin your measurement ... or you need to take time since VSYNC into account on your sound phase measurements. ...
"doktorvr" wrote:
... We are positioning the photo diode approximately at the vertical centre of the panel. We are removing the Rift's lenses to get closer access to the panel. The lowest measurement we obtained was 20ms, the highest was 34ms. ..
By "scanline" I meant "time sync VSYNC (as I clarified later), not the physical position on the display (although they would be the same for a "rolling-shutter" type display, such as a CRT). For many LCD panels, the physical position on the display may not correspond directly to time since VSYNC.
What I meant to establish in my post above was that the 16.7ms jitter can be corrected for if you always take your measurements at the same phase (scanline) of the 60Hz frame update interval.
And thanks for the direct link to the full document. :D