Marking the centroid

Dear Members,

I have just started using the ImageJ program to make measurements on
xrays. It has been a slow but steady progress.

I use mainly the ROIManager macro and the MeasureAndxyzLabel macros to
do the job. I am getting stuck at one point. I am aware that the
centroid of a circular selection can be determined by the x and y
values. Is there a way to mark the centroid and label it? This is
central to my work of measuring angles and lengths on the xray.

Thanks in advance.

Biswajit D Baruah
aka orthodoc