SOC 400T Field Use Protocol
Digital Imaging and Remote Sensing laboratory
Chester F. Carlson Center for Imaging Science
Rochester Institute of Technology
54 Lomb Memorial Drive
Rochester, NY 14623-5604
Version 0.3
18 July 2004
REVISION HISTORY
VERSION
DATE
AUTHOR
PURPOSE
0.0
11/1/2002
Rob Kaiser
Original
0.1
12/11/2003
Rob Kaiser
Editing of original.
0.2
4/12/2003
Lon Smith
Additional editing of original and addition
of R.I.T. specific forms and operational
procedures. Submitted as DRAFT for
review prior to field collect.
0.3
7/18/2004
Lon Smith
Editing of images.
1
1.0 Introduction
This document defines the protocol for performing infrared spectral reflectance
measurements in the field. The fundamental theoretical principles covered in this
document apply to general measurements made in the SWIR, MWIR and LWIR region of
the electromagnetic spectrum. More specifically, this protocol will define the use of the
Surface Optics Corporation SOC 400-T reflectometer which measures infrared radiation
from 2.0-25.0 microns with direct contact to the materials surface.
Documentation of metadata is recorded and reported differently by each measurement
group and may be dependant upon the requirements of each given collection event.
Examples of the various metadata formats will be illustrated or referenced.
The measurement of a material’s spectral reflectance in the field requires careful and
thoughtful attention to detail. In the Infrared region, a material’s spectral differences are
not readily apparent to the observer, as is the case in the visible region. An understanding
of phenomenology, instrument operation and environmental effects will have a direct
effect on the quality of the reflectance measurements. For these reasons, the personnel
collecting ground truth spectra in the field must follow a protocol that will allow
investigators to produce a spectral library of consistent and known quality.
It is also assumed that operators of the measurement equipment have had sufficient
training to properly operate the instrument according to manufacturer’s instructions. It is
important to note that this document is by no means meant to replace the manufacturer’s
instructions. Rather, it is intended to provide further specific guidance on the field usage
to insure high quality and consistent data.
Finally, this documentation is a “living work”. Performing optical radiation
measurements of this sort are dynamic and the conditions which spectra are collected in
the field are constantly changing. The methods and procedures used to collect spectra are
in a state of continuous improvement. This being true, this document needs to provide
fundamental measurement theory and the currently applied methodology from which
investigators will start when they go to the field. For a specific class of targets that has
been previously measured, this document serves as a historical set of guidelines from
which one can reference specifics of how measurements were conducted. For new
targets, it educates and reminds the investigator of the relevant phenomena that they need
to keep in mind while collecting spectra. New or improved methods will be reflected in
this document as they are developed.
2.0 Background
In general, the electromagnetic spectrum of interest to most ground truth measurements is
broadly defined from 0.38µm - 1000µm. This spectrum is divided into regions that are
defined by the materials characteristics and behaviors as a function of wavelength. This
electromagnetic energy can either be reflected, absorbed, transmitted through an object or
in the case of the infrared, the material can itself be a source of emitted energy.
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In the case of incident radiation, the sum of the reflection, absorption and transmission
interactions will account for 100% of the energy:
1=ρ+a+t
Where,
ρ = reflectivity
a = absorptivity
t = transmissivity
However, there are no materials that exhibit pure absorption, transmission or reflection
found in nature. Some objects have mirror like surfaces that have high reflectance values
just as there are objects which are opaque have very little transmissivity.
When an object is a perfect absorber, it is known as a blackbody. A blackbody can be
defined as an object that absorbs all incident energy. A blackbody is not only a perfect
absorber but is also a perfect energy emitter at a given temperature. Kirchoff’s Law states
that when a blackbody is at equilibrium, it will emit and absorb equal amounts of energy.
At equilibrium:
a=e
Since:
1=ρ+a+t
Therefore:
e = 1 – (ρ + t)
Where,
e = emissivity
a = absorptivity
Emissivity can be defined as the measure of the ability, or efficacy, that an object or its
surface can emit infrared energy. It is a ratio of the objects radiant energy at a given
temperature to that of the energy emitted by a blackbody at the same temperature.
Emissivity:
e = Wo / Wbb
Where,
Wo = the total radiant energy emitted by an object at a given
temperature.
Wbb = the total radiant energy emitted by a blackbody at the same
given temperature.
The hotter an object becomes, the more infrared energy is emitted. The Stephan –
Boltzmann Law defines this relationship:
W = e σ t4
3
Where,
W = the radiant energy in watts per square centimeter (W/ cm2)
e = the emissivity factor
σ = the Stephan – Boltzmann constant (5.67 x 10-12 W/cm2K4)
T = the temperature measured in Kelvin (Celsius + 273°)
The emissivity and reflectivity of an object are related. The sum of the emission and
reflectance is one.
1=e+ρ
Therefore, if one can measure the reflectance of an object, the emissivity can be defined
as well.
The visible, near infrared and shortwave infrared (VNIR/SWIR) region is defined from
0.38 µm - 2.5 µm. This region is often times quantified by measuring the reflectance of
the target material with consideration of the energy from background objects and the
atmosphere. The infrared MWIR and LWIR region for the purpose of this field
measurement protocol will be defined and limited to the spectral region beyond 2.5µm 25.0µm.
There also exists a cross-over region that is composed of both the reflected and selfemitted energy from the targets as well as the background objects and the atmosphere.
The commonly accepted cross-over region where the reflected and emitted energy are
equal contributors is said to be between 3.5 and 4.2 µm for most targets at ambient
temperature.
Under certain measurement conditions, specifically when the source for the
measurements is the sun and the atmosphere effects of the measurement process, the
specular reflectance can be significant. One example would be the measurement of a
smooth surface when the detector is at or near the specular reflection angle of the source.
The energy measured can still contain a large reflective component in the cross over
region. The degree of the reflectance component is a function of surface texture, sensor
geometry, specular reflection angle for the source, the reflectivity and emissivity of the
material, and the background temperature.
Certain instruments require consideration of the background materials and surrounding
atmosphere which act as secondary energy sources and attenuators due to absorption,
reflection and scattering. In general, when making infrared measurements, all objects
should be considered a source of energy including the atmosphere which contains gases
which will tend to emit energy in the same narrow bands in which they absorb. These
emission bands are sometimes identified as “continuum emission” regions. Beyond the
CO2 absorption band ending at 4.4 µm, the reflected component is negligible in most
instances.
Suffice it to say, there are many factors that can influence infrared measurements such as;
the meteorology, solar loading combined with a target’s broadband absorptivity, wind
speed which can cool the surface layer of the material where a majority of the infrared
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emitting occurs and will result the parameters, which are of major consequence in making
sound measurements.
The spectral radiance field which reaches the sensor has many components. This
particular protocol defines measurements with an instrument that utilizes an internal
source and is made with intimate contact to the material being measured thus many of the
components will not be considered since they primarily effect non-contact, solar
dependent instruments. Parameters, for MWIR and LWIR measurements using solar
illumination are defined in the SITAC, “Infrared Field Spectra Collection Protocol”
(Salvaggio, 2003).
Therefore, this protocol does not consider the effects of down-welling and upwelling
radiance but the topic deserves to be briefly mentioned. When measuring with an
instrument that can be influenced by these parameters, one must consider these as sources
of noise that will affect the measurement results. The temporal stability due to downwelling radiance is not necessary to address since the instrumentation defined for this
protocol is independent of the background radiance sources from the ground.
Similarly, the contribution of objects near the surface being measured will not be
considered since the reflected and emitted radiance from these background objects can
not be detected the instrumentation supported by this protocol.
Environmental conditions can cause changes in the measurements. Extreme temperatures
alter equipment performance. Dry rather than humid environments are desired when
measuring in the infrared to minimize the contribution of these terms. Water vapor is also
a primary contributor to atmospheric self-emission and scattering.
3. Ground Truth Collection
A “typical” ground truth spectra collection in the 2.5µm - 25µm region is composed of
the collection of several measurements to assure that the data that you are after is
extractable. In order to determine the absolute spectral emissivity of a target in the
laboratory or the field, the following phenomena need to be measured: a) the downwelling atmospheric and background radiance which is incident upon your target, b) the
temperature of the target you are measuring (if possible), and c) the radiance field leaving
the surface of your target. In addition, radiance values from a certified blackbody
calibration source are desirable in order to calibrate the instrument for subsequent
radiance measurements. The blackbody’s temperature is usually varied so that the
spectral radiance from these known sources will surround that collected from the actual
target. This allows for a good calibration provided the instruments response is linear
between the two known radiance levels at each wavelength.
If these measurements are made and the distance between the ground sensor and the
target is small (typically less than a meter), then a good estimate of spectral emissivity
can be made. Two assumptions are usually made in this scenario, the first is that the path
radiance over this one-meter path is negligible and the second is that the transmission is
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unity. In both the MWIR and LWIR regions, these are reasonable assumptions and
contribute very little to the error in derived spectral emissivity. While this sounds easy
enough, accurate measurements are not simple to make and attention needs to be paid to
the unique phenomena in the emissive portion of the spectrum, which many remote
sensing professionals are not used to.
3.1
General Considerations
In order to make accurate, repeatable ground-based measurements of radiance in the
MWIR and LWIR portions of the spectrum, the following list of items needs to be
considered during field collection campaigns.
1) A blackbody calibration should be conducted for every target that is measured or at
least every 10 - 15 minutes to reduce the effect of instrument drift. Instruments drift
when they undergo temperature changes. Temperature change will almost certainly
happen in the field due to the variable environmental conditions present. If a
temperature-controlled instrument is available, then this is preferable to a noncontrolled model. An instrument should be controlled to within 0.1°C between
calibration and actual target measurements.
2) The instrument requires a warm-up period of 15 – 20 minutes to be properly
stabilized. The instrument may be turned on and purged while being transported to
the field to expedite the measurement process.
3) In regards to instrument intensity calibration, a specular gold reference artifact used
to calibrate the unit should be used in the same relative position as the measurement
to minimize differences between the calibration and the measurement process. The
aperture should be overfilled when calibrating or measuring unknown surfaces.
4) The wavelength accuracy of the instrument should be verified at the beginning and
end of each day of collection. It is suggested that spectralon impregnated with rare
earth elements be utilized. At this time, any agreed upon material can be used that has
significant spectral features in the wavelength region of interest. An example of
material used in the past is a blue plastic tarp.
5) Measurements are best made after the morning dew has evaporated from the targets
surface. One should consider shading the instrument from direct sunlight to prevent
negative effects of thermal absorption by the instrument.
3.2
SOC-400T Measurement Specific Considerations
For the SOC-400T reflectometer owned and operated by the personnel at the Harris and
Rochester Institute of Technology, there are some more specific considerations that one
should address. These are:
1. Purge the SOC-400T. The SOC-400T should always be purged. This may be done
with dry air, the FT-IR purge gas, or compressed nitrogen gas. Dry air is used in the lab
to minimize expense, while compressed nitrogen is used while performing field
6
measurements. The purge rate is nominally set to approximately 6 liters per minute. This
flow rate can be attained by setting the flow meter at 40 while the pressure on the gauge
is at 35 psi.
Note: It is necessary to make sure that the purge cable is not being interfered with so that
a clear purge flow is allowed.
2. Select an appropriate energy source. Three power supplies are provided: one for AC
wall power with a transformer, one for car-cigarette lighter operation, and one for
12VDC battery operation. Select the appropriate cord for the situation. Connect the
power cord to the power supply (wall outlet, cigarette lighter, or battery.)
Note: For battery operation, the Red Lead should be connected to the Positive terminal.
Connect the power cord to the measurement head.
3. Energize the SOC-400T by depressing the white button on the bottom of the SOC unit.
This button will be illuminated and depressed when the SOC-400T is powered on.
Turning the instrument “ON” initiates the “warm start” which charges the interferometer
and the detector itself. The SOC-400T should be given 15 minutes warm-up time after
being powered on.
Note: Initiating a “cold start” requires that the instrument not be used for two (2) hours
after it is first plugged in.
4. Instrument Control and Communications occurs via an USB cable which must be
properly connected before the computer is turned on. This USB cable plugs into center
of the bottom of the instrument itself and into the side of the laptop.
Caution: The connector to the laptop will occasionally allow the USB cable to slip out. If
this happens and the computer loses communication with the SOC 400T this point the
laptop must be restarted.
5. Power up the computer and initiate the SOC-400T software. Sign on using the
appropriate username and password.
6. Select a directory for the spectra files collected to be placed after collection. The
directories are found in C: -> SOC-400T. A directory can either be selected or created
by, File -> New Folder, and then naming the folder.
7. Create a folder in the work area of the SOC-400T control laptop. Name it
YYYYMMDD. Individual filenames for the spectra collected for that day are defined and
associated with the metadata. These names may be established by the customer or a
collection team member.
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8. Calibrate the SOC-400T prior to taking each measurement. The SOC-400T is
calibrated by placing the reference standard face-down over the aperture. Currently this is
done when the instrument is in its vertical position. The calibration command is found
under Measurement -> Calibrate SOC-400T.
The calibration file name is the same as the sample being measured. This name should be
limited to 8 characters and a digit indicating the number of the measurement, i.e.
RedBarn1, RedBarn2, and RedBarn3.
The calibration file itself will have an extension of “_cal”, i.e. RedBarn1_cal,
RedBarn2_cal, RedBarn3_cal.
9. Establish the number of runs and scans per run. Currently, it has been found that 10
individual runs of 10 scans per run provide the best tradeoff of measurement quality as a
function of time and enable in-house quality control software to verify the quality of the
data.
10. Select Instrument Measurement Parameters.
Chopper Reference is set to: the Single-Beam option for both the Chopper
Reference and the Sample.
Gain should be set at: 1.
Resolution is set to: 4
Zero Filling is set to: None
Apodization is set to: Triangle
Phase Correction is set to: Mertz
Spectral Range is normally set to: 2.00 - 25.00 Microns.
11. Press “Collect” to initiate Calibration. Wait for calibration to be finished.
12. Remove the calibration reference standard at the end of calibration.
13. Place the sample in contact with the instrument.
14. Press the “S/R” button in the upper left part of the screen or go to Measurement ->
Measure Total Reflectance to open the measurement window.
Note: By calibrating prior to each measurement, the Sample File Name can be left the
same as the calibration file name. It will save over some of the reference files but this is
acceptable. The calibration spectrum referenced must be changed to the calibration
8
spectrum that was just created. This is done by selecting the new Cal File from the
library of files.
15. Select on the button adjacent to the Cal File text box to browse for the proper “*_cal”
file. The other options should stay the same as they were during calibration.
16. Press “Collect” to start making a measurement. The spectra will be saved in the
directory that is selected at the time of measurement.
17. Repeat the calibration and measurement steps 8 - 16 for each sample.
18. The spectra collected are saved as *.spc files. These must be converted to .txt files
for data analysis. Select each calibration (_cal) file and spectra file one by one and save
each as a text file. These files are then placed in the appropriate storage media. A date
folder should be created that contains an “Unprocessed Data” folder and a “Calibration
Files” folder. The spectra files and the calibration files go in these folders respectively.
3.4 SOC 400 Instrument Operational Specifics
The SOC-400T is a “hand-held” reflectometer for characterizing the reflectance spectrum
of solid surfaces (See Fig.1). The SOC-400T integrates a small rugged FTIR
spectrometer with a 1650K “thermal-globar” illumination source. It measures the nearnormal, total (integrated) Directional Reflectance as a function of wavelength. For
opaque solids, total directional reflectance equates to one minus the sample emissivity.
The unit operates over the spectral region of 5000 - 400 cm-1 (2µm - 25 µm) with spectral
resolutions in reciprocal centimeters selectable from 1 cm-1-32 cm-1.
Figure 1. The SOC 400T Spectral Reflectometer.
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The SOC 400T contains its own built-in illumination source. This allows the unit to
collect quality spectral data in the MWIR (3µm – 5 µm) region where passive
instruments perform poorly due to insufficient thermal emission and solar reflection
signals.
The instrument is controlled using Windows based software operating on a standard
notebook computer. The operation is menu driven offering end-to-end data collection
from a single dialog, including measurement of the internal calibration standard.
The SOC-400T is suitable for both lab and field use. In the field it can be run off
batteries and is sufficiently robust. It uses a room-temperature DTGS detector, freeing
the user from requiring coolants like liquid-nitrogen. Weighing 23 lbs and requiring a
laptop, a battery belt, and a small tank of dry nitrogen for purging, the unit is awkward
for a single operator, but can be easily operated by a two-man team.
For this field guide, it is assumed that the following ancillary equipment (not supplied by
Surface Optics Corp) is available:
1) A digital camera.
2) A handheld GPS unit.
3) A PDA, second laptop or paper documentation for metadata collection.
4) Bottled dry nitrogen for purging.
5) SOC -400T compatible power cords (custom made) for battery and cigarette lighter
operation.
6) SOC-400T Support Fixtures (optional)
3.3 Principles of Operation
The SOC-400T measurement head has 5 primary components: a thermal source, an
interferometer, integrating optics, a detector, and a chopper / reference (See Fig.2).
10
Figure 2. SOC 400T block diagram.
Collimated IR Beam
Detector
Flat mirror
Dual CPC
Motor
Parabolic
Mirror
Gold Plated Blade
Sample
The thermal source is a 1650K silicon carbide glowbar. It provides a greybody source of
illumination over the full spectral range of the sensor. The light from the glowbar is
collimated prior to entrance into the interferometer.
The interferometer is a (Michelson) Fourier Transform Infrared (FTIR) interferometer
(See Fig 3.) manufactured by MIDAC corporation. It modulates the illumination
provided by the glowbar prior to the light being incident on the sample. The collimated
beam of infrared radiation comes from the Michelson interferometer. It is reflected off a
parabolic mirror, which slightly focuses the beam. The flat mirror directs the beam onto
the sample. The size of the beam illuminating a spot on the sample is 0.5 inches in
diameter. The beam comes at about 20° off normal.
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Figure 3 Block Diagram of Interferometer
The infrared beam coming from the interferometer is collimated and modulated by the
moving mirror of the interferometer. The beam modulation is directly applicable to the
issue of separation of the illuminated and the radiated energy. The energy radiated by the
sample is measured by the detector as a DC signal. The energy reflected off the sample is
measured by the detector as an AC signal. The utilization of the interferometer allows for
energy separation and eliminates need for a chopper.
The reflected energy is collected by a system of double CPCs (Compound Parabolic
Concentrators). The system of two CPCs allows for collection of all rays reflected from
the sample and for concentration of the rays onto the face of the detector. The detector
used in the prototype is a 10 mm pyroelectric deuterated triglycine sulfate (DTGS) midinfrared detector. The protective window on the commercially available detector was
removed to minimize reflections from it and accumulate as much energy as possible.
The measurement of the Directional Reflectance requires a very stable spectrometer. The
stability of the measurement is achieved by implementing the automated reference
measurement. The measurement of spectrum with the FTIR is a two-step process. First a
spectrum called background is collected, and then the spectrum called sample is recorded.
The background spectrum is recorded off a standard or a reference material (See Fig. 4).
In the reflectance measurement this is usually a gold plated sample. The SOC-400T
measures automatically the spectrum of a reference, and the measurement process is
optimized for compensation of any possible drifts in the instrument’s signal strength.
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Figure 4 Schematic of the Reference Blade.
A motor located next to the cones collecting the reflected light moves a reference blade.
There is hole within the blade. The diameter of the hole is 0.5 inch and when the hole is
placed inside the lower cone, it allows the beam to illuminate a spot on the sample. This
is the sample measurement position. When the hole is removed from the cone, the
illuminating energy is reflected off the gold plated blade. This is the reference
measurement position. The motor moves the blade between the reference and the sample
position. The reference is measured for a few seconds and then the sample is measured
for a few seconds. This two-step process is repeated several times. The measurements in
both positions are separately collected and averaged.
The SOC-400T measures the reflectance of samples by measuring the spectrum of the
sample (Ssample) and dividing it by the measured spectrum of the reference (Sreference),
located on the chopper blade. If the zero option is turned on then a zero spectrum is
subtracted from the sample and reference before performing the ratio. This ratio is
multiplied by a calibration spectrum. The resulting spectrum is the reflectance of the
sample.
Rsample  Scal
S sample  S zero
Sreference  S zero
where:
Scal
Rsample Sreference Ssample Szero -
Calibration spectrum
Reflectance spectrum or reflectance value of the calibration sample
Measured reflectance spectrum of the calibration sample
Measure reflectance spectrum of the reference material (chopper)
“zero” spectrum recorded with no sample in front of the measurement
port.
The sample and reference spectra are computed from the Fourier transform of the
summation of several interferograms. With each successive interferogram that is added,
the signal-to-noise of the final measure is improved. The value of “Number of Runs”
field multiplied by the value of the “Scans per Run” determines how many
13
interferograms are actually collected and averaged. To reduce drift in the system, several
reference spectra are measured off the chopper and then several sample spectra are
measured off the sample. We call those two consecutive collections a run. The number of
collected spectra in one run is determined by the value of “Scans per Run” field. Those
collections, Runs, are repeated several times and all the data collected is averaged. The
“Number of Runs” field determines how many times this is repeated.
It should be noted that the SOC-400T calculates directional hemispherical reflectance,
which differs from the diffuse reflectance reported in most spectral libraries by a factor of
pi.
  1
1

Rsample
The process of calibration eliminates the spectral characteristics of the optical elements of
the instrument (source of infrared energy, mirrors, beam splitter, detector, chopper), and
atmospheric absorptions of infrared energy. The SOC-400T measurement quality is a
function of calibration frequency. The unit may be calibrated after each relocation or
break in application of the purge gas, once an hour, or at the most extreme level before
each measurement. The frequency of calibration is subjective and is determined by the
operator based upon the instrument settings, environmental conditions and other
measurement factors. Essentially, calibration frequency is to be determined by
experience and the needs of the customer. The external reference artifact is used in
addition to the chopper blade reference.
The SOC-400T is most often oriented with the sample in the “Vertical Up” position.
Studies are in process to examine the calibration effects with the sample holder in the
“Vertical Down” and “Horizontal” positions. Place the specular (mirrored) gold reference
on the sample older, gold surface down. Select Measurements / Calibrate SOC-400T
from the menu.
A SOC-400T calibration “dialog box”, similar to that shown in Figure 5 below will
appear.
3.3.1 Meta Data Collection (Object)
1) Photograph the object being measured.
2) Record the latitude and longitude of the object from the GPS receiver.
3) Record the remaining object-related Metadata. A general table maybe used or a
specific form such as the RIT SOC-400T Metadata Form (See Table 1) maybe used.
SOC 400T Data Sheet
Initials
Date (YYYYMMDD)
Location
Page
14
LES
20040812
Rochester Institute of Technology
Subject
Classification
Subject Automobile BAK-8708 NY
Classification
Paint on Metal
Weather:
Photos:
___Natural
X Man Made
Classification Information
1.Chevrolet
2. Silverado
3. 2001
3.Hood
5 Blue
Excellent Condition
This measurement was made in the center of the hood after
the auto was cleaned and dried.
Other Descriptions:
Measurement
GPS Way Point
Catalog Item:
1 of 1
"22
Time
Temperature 76
%RH 38
14:02
Wind Speed 5 MPH NNE
Subject 12
General Location 14
Flagged Area 13
Taking Calibration 15
Taking Sample 16
Other ________
Calibration File
Name:
BAK-8708 NY_CAL
Comments:
Spectra File Name:
__1. __2. __3. __4. __5. __6. __7. __8. __9. _X_10.
Paint reflectance spectra measured in Lot F of RIT. Surface was not
scratched.
SOC calibrated and measured in horizontal position.
Table 1. RIT Metadata Form.
3.3.2 Spectral Collection
Select several points on the object to collect spectrum. Select at least 3 collection points
for each unique material type. Try to find collection points where the SOC-400T will
be supported in a stable position.
1. Take a photograph of the collection point.
2. Record the collection point metadata.
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3. Calibrate the SOC-400T. Select Calibrate from the pull down box in the SOC-400T
menu. The “normal” parameter values in the calibration “dialog box” are very similar to
that of the measurement “dialog box” (See Fig 6) are given in Table 2.
Field
Save to
File name
Memo
Use Sample Directional Hemispherical
Reflectance…
Use Constant Sample Reflectance
Zero Spectrum
Value
enter working directory
YYYYMMDD
Blank
Unchecked
Checked, 0.982 for value
Unchecked
Save Chopper reference interferogram
Unchecked
Save Chopper reference single beam
Save Sample interferogram
Save sample single beam
Display during scanning
Number of runs
Scans per run
Gain
Resolution
Spectral Range
Zero Filling
Apodization
Phase Correction
Unchecked
Unchecked
Unchecked
Interferogram
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4
1
2
25 to 2
2x
Triangle
Mertz
Table 2 Parameter Values for the SOC-400T Calibration.
4. Collect the spectra with the SOC-400T. Select Measurements / Measure Total
Reflectance from the menu as per the Sequence of Events (3.5).
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Figure 6 Measurement “dialog box”
After the last sample on an object is collected, disassemble the system for transport to the
next major object to be measured, recalibrating for each new object.
3.4 Post Collection Processing
1) Download the metadata from the PDA and camera to a computer equipped with a
CD-writer. Write a CD with the metadata and label it “Meta data from ____” with
the date filled in the blank or use a hard copy format. Delete the metadata from the
PDA and the computer after the CD has been cut.
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2) Copy the spectral data from the SOC-400T control laptop to a CD using the CDwriter and supplied software. Label it “Spectra from ____” with the date filled in the
blank. Delete the spectra from the laptop after the CD has been cut. Perform any
defined quality control statistics that are desired.
3) Mail the information and media on separate days to the user defined addresses.
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