Instruction Manual

Chemometrics
NIRCal 5.5 Manual, Version A 91
3.5.2 Available Pretreatments
Pretreatment
Type
Short
Normalization
by Closure*
ncl
by Maxima*
nma
by Sdev*
nsd
to Unit Length*
nle
between 0 and 1*
n01
MSC Amplification * **
ma
MSC Full* **
mf
Divide by Spectrum
div
Standard Normal Variate*
SNV
Variance Scaling**
vs
Offset
Subtract DC*
dc
Shift Negative to Zero*
n2z
MSC Offset* **
mo
Add constant
+c
Mean Centering **
mc
Subtract Spectrum
sub
Smoothing
Average 3 points
sa3, sa3g2
***
Average 9 points
sa9, sa9g2
***
Savitzky-Golay 9 points
sg9, sg9g2
***
Derivatives
1st BCAP 5 points
db1, db1g2
***
1st Taylor 3 points
dt1, dt1g2
***
1st Savitzky-Golay 9 points
dg1, dg1g2
***
2nd BCAP 3 points
db2, db2g2
***
2nd Taylor 3 points
dt2, dt2g2
***
2nd Savitzky-Golay 9 points
dg2, dg2g2
***
2nd Taylor 3 points, Segment5, Gap5 (Linear
Filter - with fixed coefficients)
ds2, ds2g2
***
3rd Taylor 5 points
dt3, dt3g2
***
Transformation
Absorbance Log
10
(1/x)
log
Absorbance inverse 1/(10
-x
)
ilg
2nd Derivative/Logarithm
SDL
Kubelka Munk
kmu
Square x
2
sqr
Reciprocal 1/x
1/s
Filter
Linear Filter - with editable coefficients
flt
* These pretreatments are wavelength dependent. The used wavelength is the selected calibration
wavelength, or can be edited in the NIR-Explorer under Pretreatments.
*** g2 stands for Gap2-filtering. These pretreatments have been adapted for improved performance for
N-500 spectra.