The software needs to be calibrated before using.
Calibration procedure:

1. Scan a conventional ruler using the same scanner sittings, which you have used to scan the objective leaves, i.e. resolution, size ratio ...ext.
2. Save the ruler image as bmp file.
3. Use "open" button (1) to open the ruler image file which was saved in previous step.
4. Click the mouse exactly on 0 point on the ruler then move the mouse and click on other point on the ruler scale e.g. 6 cm. The covered distance will appear roughly (Uncalibrated). To make it more accurate, repeat the previous action with the same start and end points (i.e. click on 0 point then click on 6 cm point). The average of these measurements, SD and SE will appear to you. Repeat this action until be satisfied with the average. Use "Del" button (15) to delete inaccurate (irregular) measurements and "Reset" (14) button to clear all measurements.
This step is very important and seriously affects the accuracy of the final results of the software therefore make it carefully. To enhance accuracy, use as much distance as it possible on the ruler.
5. Click on "calibrate" button (18), a calibration form will appear. Put the exact length of the measured distance and select or set the unit (mm, cm or inch ext.). In our example, to put your scale in cm put the distance as 6 and the unit as cm. To put the scale in mm put the distance as 60 and the unit as mm and so on. The calibration form was also provided with some fields to save remarks concerning scanner sitting such as resolution and size ratio. These remarks will help you to save and reuse this calibration later.
2.6. Use button (19) to save current calibration.
Next time when you use the same scanner sitting you can open and reuse the saved calibration via button (20).

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