Metrohm NIRS Analyzer PRO - Manual (Page 61)

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the 100% reflectance level, though this is not shown on the correction plot. By applying this
mathematical correction, sample spectra appear as if taken using an ideal 100% reflective
background reference.
When correcting the reference, there will always be slight correction differences due to fiber position,
placement of the standard, temperature, dust, and other factors. Normally the correction will be
good to within several hundredths of an absorbance unit, as illustrated above. Math treatments are
used to correct for the resulting minor baseline effects.
NOTE: We advise removing the standards from the sample window when not in use. The intense
light beam can warm the standards considerably, which will change their photometric response.
Please place the standards on the window only for current testing, and remove them promptly when
finished.
13.2.3 Wavelength Certification
This test verifies that the wavelength scale of the Analyzer PRO meets parameters specified by the
U.S. National Institute of Standards and Technology (N.I.S.T.) for NIR wavelength response using rare-
earth standards.
1. Click on “Analyzer PRO Setup/Diagnostic”, then
“Run Wavelength Certification”.
2. The default number of scans is 10. The default
selection is “Wavelength Standard Analyzer PRO”.
Click “OK”.
3. The XC-2400 Standards set contains a mini-CD
with the standards file on it. Click on this file,
then click “Open”.
Vision initiates the test.
4. Vision requests that the user place the
wavelength standard onto the probe.
Do not click “OK” yet.