Why Do I See Oscillations (Sine Wave) In My Data; What Are These Large Noise Bands In My Data At 1400Nm And 1800Nm; What Are These Upward Or Downward Spikes In Vnir Data; B.1.12 What Are These Steps In My Data - ASD FieldSpec 3 User Manual

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B.1.9

Why do I see oscillations (sine wave) in my data?

B.1.10 What are these large noise bands in my data at 1400nm
and 1800nm?
Figure B-2
B.1.11 What are these upward or downward spikes in VNIR
data?

B.1.12 What are these steps in my data?

ASD.Document 600540 Rev. C
Your light source may use AC power. A single SWIR band is about 100 ms. If
you observe six (6) waves in a single SWIR, the AC light source is the cause.
Water vapor in the atmosphere absorbs light in those bands.
Examples of water vapor absorbing light.
These result from artificial light sources, in particular fluorescent lights
The instrument is fed spectral data through 57 fiber optic strands. Each strand
has its own field of view (FOV). When the end of the fiber cable is held
relatively close to the sample, each strand's FOV may be limited to different
features of the sample which can result in the stepped data.
Hold the end of the fiber cable further away from the sample to allow the
FOV of the individual strands to overlap and mesh together.
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Appendix B Reference Information
FieldSpec® 3 User Manual