Another marker appearing for no reason

[royb]

I work with PPT Studio 2008 with 7 PPT-H cameras and a headset, which is the only marker I use. Now, quite often in the Marker Data window, except for the head marker, it will show an additional perfectly still point (except for the head marker which is mobile - changes its location). If this additional mysterious point is perceived as marker #1 (and the head as #2), it completely ruins the movement detection.
Any idea where this additional marker/point can come from? How do I make it disappear?
Thanks a lot,
Roy

[Jeff]

This means there is some type of interfering light. That could be natural light, light from an electric device, or light reflecting off some surface. If there is no way for you to remove the interfering light you can crop out regions of the cameras' views where the light appears. Instructions for doing that can be found in the PPT documention under Adjusting Camera Settings. If you need further assistance contact ppthelp@worldviz.com.

[royb]

Thanks a lot for the quick reply
But my problem is that this interfering static light keeps appearing in different locations at different times, so I can't tell the source nor crop out a camera region. Is there something else I should do? Should I contact the mail address you posted?
Thanks a lot,
Roy

[Jeff]

Yes, you can contact us by email.