MTS Fundamental Video Extensometer - Manual (Page 18)

Fundamental Video Extensometer 18
Principle of Markers Tracking
Four Markers
Place the gage such that it is centered on the specimen (Figure 3).
Trace the four markers, by using the sites corresponding to the test chosen, using
a felt pen. The markers must be similar and have distinct edges. The markers
must be similar and have distinct edges (Figure 4). Let dry for a few seconds.
Note If the specimens are of dark color, use a white felt pen and if the
specimens are of clear color, use a black felt pen, because the software
needs a strong contrast to identify the markers correctly.
It is also possible to have self-adhesive reflective stickers on the specimen.