There has been some confusion about how to do the setup for the Area Mode in the Standard and Quantitative Analysis programs. The confusion comes about when trying to set the beginning and ending points of the scan (at location #3 below), and the fact that the software ignores these positions when entered by the user.

Problem: A user will sometimes notice that after doing a preliminary Area Mode scan, the starting and ending points are offset from their desired positions. The user will then enter new positions (#3 above) in the “area_shell” window, and saves these new settings to the database. However the next time a scan is run, those entered values are not used.

Background: The confusion lies in the fact that the starting and ending positions entered into the "area_shell" window (#3) are not actually saved in the database. What is saved is the FWHM of the peak, and some coefficients used to calculate the scans starting and ending positions relative to the peak position. Therefore if the peak position is wrong, then the starting and ending positions of the scan are also wrong.

Detailed Procedure: In order to define the proper parameters do the following.

1) Open the Peak Search window and click on "Element".

2) Enter the element of interest and set the “Cond.” to the correct spectrometer and crystal.
    This is important, because this will make sure that the proper SCA conditions are used.

3) Do a peak search with the “Area Mode” uncheck, to determine the actual peak position.

4) Now select the “Area Mode” check box (2), and make sure the correct peak position is
    displayed in the starting peak position box (1). If it is not, enter it.

5) Click on Search, to run the scan.

6) Inspect the results to determine whether the background positions (those marked by
    the red box) are suitable. If they are not, they can be changed using the procedure below.
       a) From the Utility Menu, select "Control Area Pksk".
       b) Select “Set By Mouse”.
       c) Click on both the desired upper and lower background positions on the
           previously run scan.
       d) The new offset values for the upper and lower background positions will be stored
           in boxes (5) and (6). These offset values define the background positions relative to the
           peak position and the FWHM value. Therefore it is important to have the correct peak position.

7) The software will now calculate a start and end positions for the scan relative the background
      locations.

8) The user can also now modify the step size of the scan and the dwell time at each point.

9) Store the parameters to the database by clicking on the “Add to Database” button.

Now that these parameters have been determined, the user can go to either Standard or Quantitative Analysis and set the mode to "Area" (Quantitative Analysis > Element Conditions > WDS> Condition > Time/Count > Area Mode). If it had been previously set to area, switch it back to “Time”, and then back again to “Area” The software only loads in the peak search parameters when the area mode is initially selected. Any changes to the parameters after that point will be ignored.

Side Point: If you would prefer to set the beginning and ending points of the scan directly, this can be done through: Peak Search >> Utility >> Online Deconvolution.