Thanks for the great tool. I'm currently trying to adapt it a little bit for my use, and bit of help would be appreciated.
I have a bunch of images from which I plan to grab data. However, they only have y axis reference points, so I can't calibrate them properly. The x-axis is on the same scale as the y-axis, so what I want to do is force the origins of both axes to be at the same location. Then I can force the horizontal distance (on screen) between Xo and Xmax to be the same as the vertical distance between Yo and Ymax. However, I don't really understand how the locations of the calibration points are stored and used, so I'm having trouble.