View Full Version : help with reflection in video analysis

Chris Hamilton (utmb)
09-19-1995, 06:46 AM
We have an interesting problem, and would welcome any advice.
Of course, we'll post all replies to the group.

We are doing kinematic analysis of a number of body parts.
We use a Motion Analysis system to collect the data, with
3 cameras and a relatively standard set-up. During some recent
work, we've had problems with too much reflection from the skin
surface which confuses the computer in picking up the marker.
Despite tweaking the contrast and gains, we don't always get
all the markers (or we get whiteout).
We have tried betadine and ink, but still get too much reflection
from the surface.
Interestingly, we have not had the same problem with live people,
only cadeveric specimens.
We may need to resort to flat black paint, a solution that one
of the PIs finds unappealing (and one that cannot be used for
ongoing clinical work).

Thanks in Advance

Chris Hamilton, MD
University of Texas Medical Branch at Galveston
Department of Orthopaedic Surgery
Biomechanics Lab