Introduction

If you have a paper well log and you would like to recreate the log digitally (e.g., in Strater or in another well log or borehole plotting software) or need the information in LAS format, you can use Didger. Didger can digitize well log curves from either a paper log on a digitizing tablet or from a scanned image, resample the curves to a specified interval, and export to an LAS file.

Digitizing From a Tablet

If you have a digitizing tablet, you can put the paper well log on the tablet and begin the digitizing process. 

1. See here for instructions on calibrating a digitizing tablet.
2. Once the calibration is finished, click Draw | Polyline and then digitize the well log on the tablet using the tablet puck or stylus.
   
   
   
   
   Use the Draw | Polylines command and trace the log on the tablet
   using the puck or stylus. The digitized log will be transferred
   to the Didger project window as you digitize.
   
   
3. Once the log is digitized, select the digitized polyline on the screen and click Draw | Resample Polylines.
4. Choose to resample along the Y axis, and choose the starting, ending, and increment values. Uncheck the check box next to Create New Line and click OK and the line will be resampled. You can see in the Coordinate Manager that the coordinate values are resampled to the specified interval.
   
   
   

   Choose to resample along the Y axis and specify the
   starting, ending, and increment value.

   
   
   
   

   Once the polyline is resampled, you can see the coordinates in
   the Coordinate Manager showing the Y value incremented
   by the specified value.
   
   

5. Once the polyline is resampled, click File | Export and export the polyline to an LAS file. You have the option of including Well Info and Curve Info in the LAS Export dialog box.
   
   
   

   You have the option of entering Well Info and Curve Info
   when exporting a resampled polyline to an LAS file.

Digitizing From a Scanned Image

If you do not have a digitizing tablet but you have a scanner, you can scan in the paper well log and use the bitmap image in Didger. This process takes a few more steps than digitizing it from a digitizing tablet:

1. See here for instructions on calibrating a scanned image.
2. Now that the image is calibrated, you can digitize the well log. If the log is a different color than the grid lines, you can use the Image | Vectorize Image command to automatically digitize the line. If the log is the same color as the grid lines, you will then use Draw | Polyline to digitize the log.
   
   

   Digitize the well log by going to Draw | Polyline and then tracing over
   the log with the mouse while holding the left button down.

3. Click File | Export and export the polyline to a vector file format (e.g., Golden Software Interchange, *.GSI).
4. Go to File | New | Import Vector and import the vector file back into Didger.
5. Once the log is digitized, select the digitized polyline on the screen and click Draw | Resample Polylines.
6. Choose to resample along the Y axis, and choose the starting, ending, and increment values. Uncheck the check box next to Create New Line and click OK and the line will be resampled. You can see in the Coordinate Manager that the coordinate values are resampled to the specified interval.
   
   
   

   Choose to resample along the Y axis and specify the
   starting, ending, and increment value.

   
   
   
   

   Once the polyline is resampled, you can see the coordinates in
   the Coordinate Manager showing the Y value incremented
   by the specified value.
   
   

7. Once the polyline is resampled, click File | Export and export the polyline to an LAS file. You have the option of including Well Info and Curve Info in the LAS Export dialog box.
   
   
   

   You have the option of entering Well Info and Curve Info
   when exporting a resampled polyline to an LAS file.