Metrohm NIRS XDS RapidContent Analyzer - Manual (Page 44)

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enhance model transferability between instruments.
A photometric standard of known reflectivity (as measured on an absolute reflectance scale) is
scanned on the instrument. The internal ceramic standard is scanned. The differences of the ceramic
standard from 100% reflectivity are mapped, and a photometric correction is generated. This
correction is then applied to every spectrum taken on the instrument, to make each spectrum appear
as if taken with a reference of 100% reflectance. This assures that bright samples do not saturate the
instrument, or produce negative absorbance values.
Vision software stores the Reflectance Standard file, which is downloaded to the instrument, and is
applied as a correction to each spectrum. Follow these steps to create a reference standard:
Select Diagnostics, Reference
Standard,
Create Reference Standard.
Vision prompts for the instrument reference. The XDS RCA has an internal instrument ceramic
reference which is positioned automatically.
If Vision displays the Instrument Configuration
screen again, click “OK to accept the
instrument identification.
Vision briefly displays a dialog box which indicates that the instrument reference is being placed into
position. In reflectance, this is automatic. No user action is required.
The status bar indicates scan progress.