Advanced

Sets other parameters of the method, most notably the Subtraction and Auxiliary Signals. When invoked by the menu command, the Method Setup - Advanced dialog will open. The tab is common to all signals while performing multidetector measurement.

Method Setup - Advanced

Subtraction

Sets an automatic subtraction of a previously measured chromatogram from the currently measured chromatogram. The subtraction will be indicated in the printout with the “mathematics” inscription. Use of automatic subtraction is also shown in the Chromatogram Audit Trail.

The subtracted chromatogram is saved into the measured chromatogram, it is not simply linked to it. The changes occurring with the subtraction chromatogram thus do not influence the measured chromatogram from which the background is subtracted. The subtraction, however, does not hold its history - only last subtracted chromatogram's data is saved when it is changed, all older subtraction chromatograms are discarded.

If the chromatogram being subtracted has different number of signals than the method, only the signals present both in the method and in the subtracted chromatogram will be subtracted.

Note:

The subtracted chromatogram may be displayed during a measurement in the Data Acquisition window. It will appear in the background as a grey chromatogram.

Chromatogram

A dialog for specifying the subtracted chromatogram.

Matching

Sets the method of the background chromatogram subtraction.

No change - The subtraction chromatogram will be subtracted from the measured chromatogram without any additional amendments.

Offset Subtraction Chromatogram - The Clarity workstation attempts to “offset” the measured chromatogram with the subtraction chromatogram by shifting it on the axis X (time axis) before the actual subtracting.

Scale Subtraction Chromatogram - The Clarity workstation attempts to “offset” the measured chromatogram before subtracting by scaling the subtraction chromatogram on the time axis.

Note:

Offsetting of chromatograms is designed according to the largest peaks in the chromatogram (i.e. either the highest peak or the peak with the greatest area).

Set…

Opens the Open Chromatogram dialog for selecting the file to be subtracted.

None

Cancels subtraction of the chromatogram.

Note:

Should you wish to display e.g. the solvent only on the background of the Data Acquisition window without automatic subtraction, use the File - Set Background Chromatogram… command in the Data Acquisition window.

Column Calculations

Parameters affecting calculations on the Performance tab in the Chromatogram window.

Unretained Time

Determines the unretained peak time of used column in minutes. This parameter is used to calculate the capacity ratio.

Column Length

Determines the column length in millimeters. This parameter is used to calculate relative column efficiency.

Statistical Moments

Calculation runs based on statistical moments.

From Width at 50%

Calculation runs based on peak width at half the height and corresponding half-lengths.

Auxiliary Signals

This section of the Method Setup - Advanced tab is used for setting the auxiliary signals storing and possible display.

Note:

The presence of auxiliary signals is dependent on the directly controlled device. Some of these have auxiliary signals, some do not.

Auxiliary signal

List of available auxiliary signals.

Store

Check the checkbox to save the particular auxiliary signal to the measured chromatogram.

Note:

To display the auxiliary signals in the graph it is necessary to set their display in the Graph Properties dialog of the particular graph. It is, however, necessary to have the particular signal stored in order to be able to display it.

User Variables

Sets Method User Variables which can be used for User Columns calculations. Up to three independent variables can be set.

Name

Sets the name of the variable. If the field is left empty, default name MethodUserVar1-MethodUserVar3 would remain filled in.

Value

Sets the numerical value of the variable.