3D Calibrate

3D Calibrate

Normally the data produced by the 3D digitizer has no real units on the x and y axis. The x and y values are just incremented by one from 1 to the width/height of the image.

There may be a time where you would like more absolute values (measured) for these axis.

There are two items in the 3D window that allows you to do this. First is the calibration markers superimposed on top of the image after you enable them through the menu item 3D|Calibration marks. The other is the calibration text box. The markers have 10 graduations and internally they are broken down to 100 total.

If you know the actual distance on your image between the end points of the markers you enter this into the calibration text box. This does not mean you can measure the image on the screen unless it is actual size. It means you have to use some means of measuring the real picture. Example would be a map with a distance scale on it or measuring a picture between two reference points and using these reference points on the screen image.

Eg.    |_____|_____|      Distance = 100 and would be 1 unit = 1 point
         1               100     100 increments/100 = scale of 1

Eg. 2 |_____|_____|

          <---- 2.30---->

The distance between the ends in this example is 2.30 which could be inches, centimeters, miles, etc. Enter 2.30 into the calibration text box. Now .023 units = 1 point and 2.30 units = 100 points. This will be reflected when you transfer the data to the 2D Analysis plotter.

When you save the data to a file, the data in the file will reflect the new calibration also.

Caution: If you resize the window these values will have to be re-entered to correct for the change in the image/marker ratio.