Metrohm Vision Manual - Manual (Page 202)

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9
Master Standardization
9.1 Introduction
The objective of Master Standardization is to reduce instrument to instrument variation by declaring
one unit as the Master and matching other units (Hosts) spectrally to that Master via a
Standardization Equation. This will improve the transferability of models, both Quantitative and
Qualitative, between instruments.
In order to develop a Standardization Equation the user needs to have spectra of the same sample
(check cell) taken on both the Master and the Host instruments saved in one project. The developed
standardization equation is saved in the project database and cannot be copied from one project to
another.
Vision allows the user to develop and use standardization equations specific for each product, or to
apply a single standardization equation global to the project. It is also possible to have both a global
and product specific standardization equations in the same project. When using product specific
standardization equations, not all products in the project have to have them attached.
If Master Standardization in enabled in Vision, the hierarchy of the standardization equation search is
as follows:
1. In Data Acquisition, the project global standardization equation is applied during spectral
acquisition (if exists). Product specific standardization equations are ignored. If product-
specific standardization is necessary, it has to be done off-line or global standardization
equation for the project has to be changed every time a product is changed.
2. In Routine Analysis, if the analysis sequence starts with identification ("unknown") the project
global standardization equation is applied if exists.
Note: If the analysis sequence starts with Qualification or only Quantification is used, Vision will
apply the product specific standardization equation if exists. If it does not exist, the project global
standardization equation is applied (if exists).
9.2 How to enable and configure Master Standardization on a
Host instrument
9.2.1 Enabling Master Standardization in a project
In Data Acquisition mode, click on Configure/Options. Check the Master Standardization to activate it
in this project.
Creating Master Standardization equation
There are two methods of creating the standardization equation. The first method can be used off-
line and requires two spectra of the check cell collected on both Master and Host instruments. The
second method requires that a sample (check cell) and its spectrum taken on the Master instrument
are available in Vision connected to the Host instrument. The spectrum has to be exported from the
Master in the NSAS format.