XY calibration is not take into account in OSX M2 about webplotdigitizer

[elcolie]

Close because I am unable to reproduce this.

[nbehrnd]

These values are about the pixels of the illustration. Don't worry, continue to the point you collect the digitized data.

With four reference points*:

you get to something similar to

* My personal preference is to define reference points for abscissa and ordinate without an overlay (e.g., on the origin of the coordinate system), i.e. x1 and x2 reasonably accurate on the horizontal axis, but not necessarily as much as equally well accurate along the vertical one, for example.