# General procedure

- `Set Scale` 100um -> 171 px
- `Set Measurements...` bounding rectangle, display label, Decimals 4, Redirect none
- `Measure` and `Clear Measurements` to produce a new and clear measuremens table
- Use the `Straight` tool to draw a line thta fits into the decarburated area
- Press `^+m` to add the measurement into the table
- Repeat the process at least 50 times

![Example of measurements.](measurements-example.jpg)