Now the real work starts: whenever you click somewhere on the bitmap a new pair of x-a nd y-values is created in the data list on the right of the window. In addition a small circle is drawn on the bitmap to remind you where you have collected points already.

Click a few points and watch the list of data points grow.

What is left to do is to move along the curve to be digitized and collect as many points as desired. Before you start this real work you can free the list from previous points by Clear list and start with an empty list.

While collecting points you should know that the list of data points can be edited - in particular, wrong points (where you failed to click correctly) can be deleted. Be aware, nevertheless, that the list should not contain blank lines because this will cause errors when you process the data later.

In between the window may look like this: