Metrohm Vision Manual - Manual (Page 148)

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Click on Mode/ Quantitative
Analysis/Regression.
Select the equation and click on
Regression/Adjust Constituent (Pre-
processing).
Vision will display the window to the
left.
This window works as a calculator and
can create formulas combining various
constituents.
In our example dividing amount by
weight creates the formula for
concentration.
It can be entered by clicking on the
AMOUNT constituent, then the division
symbol, and finally the WEIGHT
constituent.
The formula on the left will be shown.
Click on Save to save the formula and
close the window. Vision will display the
spreadsheet with new constituent
values.
4. The next step consists of creating and developing a standard calibration based on spectral
data and the new constituent created as the result of pre-processing. In our example, the
regression will be performed on spectra from product CALIBRATION and constituent
CONCENTRATION. The calibration will be named CONCENTRATION. The regression can be
done using either the MLR or PLS method. This step is discussed in other parts of the manual
and will not be described here in detail.
5. In the last step, the post-processing equation needs to be created and configured. Enter the
Quantitative Sample Selection and drag product with calibration samples into the Equation
field. Select the constituent CONCENTRATION and enter AMOUNT as the equation name.
Make sure the new equation is highlighted, and click on Select/Create Equation for Post-
processing. Note that Vision adds the prefix Post_ in front of the equation name.
Proceed to Operations Method setup. Configure the Operations Method as described in the
appropriate part of the manual. Click on Quant Setup. Select the product and expand the tree
to find the equations created for product with calibration samples (please note that pre-
processing equation is not listed). Double click first the standard equation (called
CALIBRATION in this example), and then the post-processing equation. Click on Save.