r'BACKGROUND SPECTRAL 8ADIANCE / AND CONTRAST IN … · r'background spectral 8adiance / and contrast in the i nearu, m-ir, and lwir regions / ... g. c. halterman sf. a. jepson r

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r'BACKGROUND SPECTRAL 8ADIANCE /AND CONTRAST IN THE

I NEARU, M-IR, AND LWIR REGIONS /

"//• ,A COMPILATION OF~ GENERAL DYNAMICS

'3 , ,MEASUREMENT DATA

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j 1ACKNOWLEDGEMENTS

The work described in this report was performed by the following Pormona Divisionof General Dynamics employes:

G. W. Ashley

1D. W. Blay

E. 0. Buenting

L. Gastineau

G. C. Halterman

SF. A. Jepson

R. T. Long

N. H. Prentiss

L. H. Tanabe

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Absolute spectral radiance signatures of a number of natural backgrounds have beenmeasured in the following wavel ngth regions:

0 Near - UV (0.30 - 0.447)

S* MID -IR (1.5 -5.4and2.0 -5.4p)

"1 * LWIR (2- 13\

The infrared data were obtained using an interferometer with high spectral and spatialresolution while the near-UV data were acquired using a dispersive-prism spectrometer.In addition to the individizal background spectra, spectral contrast plots are presented forspatially adjacent background areas. These contrast plots can be used in conjunction withtarget spectra to derive optimized spectral regions of operation for target detection sys-

* tems, Also included are photographs illustrating the spatial appearance of the variousI background areas in appropriate wavelength bands.

V/Vj[iJ . 4

CONTENTS

Section PageI Introduction ........... 1-1

2 Instrumentation .................................. 2-12.1 Infrared Interferometer ........................ 2-22.2 Near-UV Prism Spectrometer .................... 2-4

3 I • M D ( 5 - 5 4 . 6 . . 0 . . 0 0 . 34 Phase-I IR Measurement Data (1.5 - 5.41A)............... 3-15 Phase-II UV Measurement Data (2.30 - 5 . 4 .) ............. 4-1" 5 Phase-I UV Measurement Data (0.30 - 0.44j#) . . .... .. .. . .. 5-1.

6 Phase-III R Measurement Data (2.0 - 1 2 . 8 I) ............. 6-1

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I Section 1INTRODUCTION

over the past decade, workers in the optical radiation field have expended consider-able effort in the measurement of the radiation signatures of natural background and alarge quantity of data exists, However, when onie is required to use the data in a systemapplication, certain problems arise. Most detection systems are contrast sensors andthe primary response generated from backgrounds is due to non-homogeneity or contrastswithin the backgrounds. Response to backgrounds can be calculated by spectrally sub-tracting the signatures of selected backgrounds and usinig this data in conjunction withother system parameters. This procedure has been used in the past, however, it oftenleads to erroneous results which can be particularly disastrous if one is attempting toselect an opý.ri~um spectral region of operation which will maximize target to backgroundsignal ratios. Quite often the backgrounds areas which are selected for spectral subtrac-tion are taken from spatially remote portions of the background, at different times of theday, at different site locations, or even with different instrumentation. Any of the afore-mentioned conditions (and others) can produce spectral contrast plots which are unrealisticand maost often, unduly severe.

In view of the aforementioned problems and the desire to obtain data with higherspectral and spatial resolution, a background measurement program was initiated at thePomon Division of General Dyniamics in early 1969. The program ultimately will includethe measurement of a wide variety of natural backgrounds within three principal spectralregions of interest, 0. 2 to 0. 6, 1.5 to 5. 4, and 5 to 15 micrometers.

It is the objective of this report to presenm '. compilation of General Dynamics back-'. ground measurement data gathered during three separate field measurement efforts whichtook place between early 1969 and late 1974. Table L-1 summarizes the type and quantity

[ of data gathered during this time frame,

Table 1-1[ ~SUMMARY OF B3ACKGROUJND MEASUREMENT EFFORTS

AT GENERAL DYNAMICS, POMONA DIVISION

Number of DataMeasurement Time Spectral Background Presented

Phase No. Period Region Coveredl Scenes In Figures

[1 4/21-4/24/69 1. 5 - 5. 4p. 15 3-1 through 3-15

II 1/29-6/15/70 2. 0 - 5. 4p 25 4-1 through 4-253/31-5/19/70 0.30-0.44M 24 5-1 through 5-24

111 10/16/74 2. 0-12. 8p. 8 6-1 through 6-8

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Section2INSTRUMENTATION.

The spectral data presented in this report were taken with two basic instruments:(1) a rapid-scan, Michelson-type interferometer spectrometel (Figure 2-1), and (2) adispersive-prism-type spectrometer (Figure 2-2). A complete measurement facility washoused in the Cortez Van shown in Figure 2-3. Besides the basic spectrometers, the vanincluded a 10 kW power generator, a search/range radar, VHF/UHF communcations, anIRIG time code generator and search-control unit, a hybrid digital/analog recording sys-tem, a real-time 500 point spectrum analyzer for data assessment, and associated moni-tor and calibration instrumentation for the UV and IR systems.

Either visual-band, near-UV (0.35-0.40p), or near-Ir (0,7-0.9/A) photographs, aswell as mid-IR (3.6-5.414) thermal images of the background areas being examined, were

recorded simultaneous with the spectral measurements. The near-UV photos were ob-tained using a 35-millimeter Nikon camera equipped with Kodak Linagraph Ortho film, a200 mm quartz lens, and a Jena-Schott UG-11/BG-38 dye filter combination. The near-IR photos were obtained using a similar camera equipped with Kodak type IR-135 film,135 mm glass lens, and a Corning No. CS-57-1. 92 optical bandpass filter. The thermalimages were recorded using a Polaroid camera attachment to the CRT display of an AGACorporation Thermovision instrument. The Thermovision utilizes an InSb detector andexhibits a half-power response bandpass of 3.6 to 5. 4 microns.

0

I IFigure 2-1. Fourier Spectrometer and Control Electronics

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Figure 2-2. UV Prism Spectrometer and Control Electronics

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Figure 2-3. Cortez Instrumentation Van

2.1 INFRARED INTERFEROMETER

The general operation of the infrared interferometer can be explained with the aid ofthe optical schematic shown as Figure 2-4. A standard Michelson interferometer opticalcube is formed by the fixed mirror, the scanning mirror and the bisecting beamsplitter.These optical elements are arranged such that incident radiation entering the system isdivided into two approximately equal beams of transmitted and reflected radiation. Thereflected beam is directed to the fixed mirror and returned to the beamsplitter surface.The second beam iW transmitted to the scanning mirror and also returned to the beam-splitter surface, These two component beams recombine at the beamsplitter surface in

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either a constructive or destuctive manner, depending upon the differences in optical( ,athlengths (i.e., phase relationship). This time-varying interference pattern (termed

as "interferograin") is observed by the liquid nitrogen cooled infrared detector. Thetemporal frequency associated with the generated interference pattern is a function ofthe mirror optical scanning speed and the wavelength of the incoming radiation. Thewavelength spectrum of the incident radiation can be determined by performing a Fouriertransformation of the electrical waveform generated by the detector.

The output of a 6328 A He-Ne laser source is also passed through the optical cubeproducing a separate interference pattern which is detected by an uncooled silicon (Si)photovoltaic detector. Since the laser is essentially monochromatic, the interferogramoutput of the Si detector is sinusoidal at a single frequency, which can be directly relatedto the mirror optical scaiming speed, The laser-detected interferogram provides thewavelength/frequency calibration for the target-detected interferogram and is also usedto provide an optically linearized clock signal for conversion of the analog data to a dig-ital form (which is done in real-time with a 15 bit A-D converter).

A third optical channel consisting of a broadband, "white-light" source and an un-cooled Lead Selenide (PbSe) detector provides a reference interferogram for defining theoptical center of the target interferogram produced in the main data channel. The whitelight source (an incandescent lamp) produces an interferogram with a very sharp peakwhich occurs at zero optical retardation (the point in the optical scan at which the path-length traversed by the two split beams is equal), The location of the zero retardationpoint is necessary for certain data reduction processes which include the coherent addi-tion or subtraction of target-generated interferograms.

Specific characteristics of the interferometers, used in the background measurementsperformed to date, are presented in Table 2-1.

2.2 NEAR-UV PRISM SPECTROMETER

UV spectral measurements were performed through the use of an ITT model SF 103-R8 prism-type spectrometer as pictured in Figure 2-2. This instrument consists of twobasic parts. These are the control console and the spectrometer proper. The controlconsole contains the function controls, amplifiers, gain and filter switches, and outputconnector. The spectrometer contains the collecting optics, the monochromator, thedetector, and the mechanical components for scanning.

An optical schematic of the spectrometer is presented in Figure 2-5. Radiation iscollected by the cassegrain foreoptics which focuses the optical beam on the entrance slit.A mechanical chopper is situated between the entrance slit and the second mirror, whichdirects the beam toward the slit, to provide a carrier frequency for the resultant signalfrom the detector. From the entrance slit the beam diverges, striking a third mirrorwhich directs it to a fixed collimating reflector. The reflected, collimated radiation thenpasses through the LiF prism which disperses it. After striking a movable littrow mirror,situated in such a manner as to only properly reflect radiation to the exit slit which iscentered about a specific wavelength, the beam is reflected back through the prism to thecollimator. At this point, the collimator reverses its previous function and causes theradiation to converge on the detector after being reflected for a seventh time and passingthrough the exit slit to the detector.

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,1 I The spectrometer scans continually in a triangular waveform, alternately scanningfrom short to long wavelength, then from long to short wavelength, The scan is linear

i, with respect to wavelength in both directions and the time rate of scan may be selectedfor any speed from 0. 012 scans per second to 5 scans per second. Since wavelengthselection within the instrument is determined solely by the position of the mirror behindthe prism, a metal arm mechanically links the moving mirror to the wavelength indicatorand photo diode which creates a pulse at the short wavelength end of each scan. When the dinstrument is scanning from short to long wavelengths a second pulse is electronically in-duced into the output, providing a rapid means of determining the scan direction. The de-tector output and wavelength marker pulses are converted to a digital form in real-time(15-bit A-D converter plus level detector).I The entrance and exit slits are controlled by the same dial on the instrument. Thisdial is graduated in 0. 01 mm increments and permits manual opening or closing of theslits to a maximum of 2 mm slit width. The entrance slit has a Hartmann diaphram in

1 a stepped design to permit narrowing of the slit height.Specific characteristics of the UV-spectrometer, as used in gathering the background

data presented herein, are presented in Table 2-2.

Table 2-21 ]PRINCIPAL UV-SPECTROMETER CHARACTERISTICS

Measurement Phase II

4k Item Prior to 5-5-70 After to 5-5-70

_ Model SF -103RS SF -103RS

Detector Type 1P28, S-5 P.M. 1P28, S-5 P.M.

Prism LiF LiF

Spectral Coverage 0.20 - 0.44A 0.20 - 0.44A

, "Spectral Resolution 0. 0025M 0. 0025p

Spectrum Recording Rate 0.025/sec. * 0.225/sec. *

Collecting Optics 4.5 in. dia, F/9 4.5 in. dia, F/9

Optical Field-of-View (50 percent) G. 1x4 mra1 0. 16x4 rnrad

Modulation Frequency 4800 Hz 4800 Hz

*Note: Approximately 20 seconds required to cover the 0. 30-0. 44pregion.

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Section 3

PHASE-I IR MEASUREMENT DATA (1.5 - 5.4 • )

During the Phase I measurement effort, an attempt was made to obtain a varietyof backgrounds with heavy concentration on those which were considered most severeto an infrared system. Spectral plots from this initial phase of the program arepresented in figures 3-1 through 3-15 (Background Scenes number 1 through 15). TheBackground Scenes number 1 through 15, with letters "A" and "B" are absolutespectral signatures of the areas indicated on the infrared photographs. These plotsare referenced to essentially zero temperature (770K liquid nitrogen reference). TheBackground Scenes number 1 through 15, with letters "C" and "D" are contrast plotsobtained by computer subtraction and are plotted in both linear and logarithmic formats.All contrast pairs were confined to a spatial separation of less than 1 degree andrecorded within a 5 minute period of time. Up to 90 seconds of data (90 interferograms)

were averaged to obtain some of the data presented in this section.All of the spectra presented were measured during the daylight hours and exhibit

various amounts of solar reflected energy in the 1. 5 to approximately 3 micron region.Beyond 3 microns, the self-emission of the background areas predominates in most

cases. The H20 absorption bands are strongly evident at 1. 8 and 2. 7 microns and toa lesser extent in the 5 micron region where they appear as emission bands in most

"plots. Also the 4.3 CO 2 band appears as both absorption or emission, depending onthe particular background conditions.

Beyond 3 microns, the spectral curves show little variation from one to another, Iwhereas the radiation in the shorter wavelengths showy considerable differences within

the atmospheric window regions. These differences are reflected directly in thecontrast plots which generally indicate a minimum beyond 4 microns.

"The contrast plots can be used to calculate a system response to these backgrounds,. given the system sensitivity and instantaneous field of view. Conversely, if the system

is yet to be designed and the spectral characteristics of the target are known, the"contrast data may be used to optimize the spectral region of operation. The optimiza-tion is performed by plotting a spectral ratio of apparent target irradiance to back-ground contrast irradiance. For a maximization of target to background energy, thespectral region of operation should be confined to the narrow region (or regions)centered about the peak of the plot. The detection bandwidth of the system will be

predicated on the system sensitivity, r equired detection range and background false

alarm rate. The spectral signature used for the target should contain atmosphericabsorption as expected under typical system operation.

Depending on the system application, certain types of backgrounds may be

excluded from consideration. Certain classes of the contrast plots presented indicatetrends or characteristics which may be used to advantage in a system design.

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1. SECTION 4

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Section 4SPIASE-II III MEASUREMENT DATA (2.0- 5. 4 1)

The Phase II infrared spectra taken from 25 natural background sites are pre-sented in the following pages, (Figures 4-1 through 4-25). The near-IR photographsillustrate the spatial relationship which existed between the various pl ts while thethermal image data provides a first order feel for the appearance that these back-grounds present when integrated over the 2 to 5-micron region. Included with thedata arc the angular coordinates to the sites as referenced to the measurement loca-tion and corresponding sun angle positions. The elevation, temperature and relativehumidity data are related to the measurement location. The 25 background sites aregrouped and presented in the following sequence: clouds, sky, snow, terrain, andwater. The data presented in this section typically represent the coherent average

Sof interferograms recorded over a 10 second time period.Particular care was taken with respect to absolute calibration of the spectrometer

at each measurement site so that spectral curves can be cross-correlated, Thecalibration consisted of using a 600'C blackbody to establish the response function ofthe interferometer, a full-field 300'K blackbody for direct radiance calibration, and

a liquid-nitrogen (77'K) calibration which is used as the reference for absoluteradiance.

The actual spectra of the particular background areas are plotted from 2. 0 to5. 4 microns. The ordinate values for each plot arc automatically selected by thecomputer data reduction program and care must be exercised to observe these or-dinate scales when comparing data. The contrast or difference spectra arc plottedfrom 2. 6 to 5. 4 microns. excluding the high solar radiance values normally expe-rienced in the 2. 0 to 2. 6 micron region. The difference plots can be positive ornegative with respect to zero depending 'on the order in which they were subtracted.

Sites number 25,8 and 6 (Figures 4-25, 4-8, and 4-6) have been selected for abrief discussion of the infrared spectral characteristics which are general to mostof the backgrounds presented in this report. The primary interest in site 25 is thespectral signature of the sunlit lake whichI is shown in plot number 1. The spectrais the combined result of strong specular solar reflection, (which predominates inthe region from 2. 0 to about 4 microns) and the self-emission of the warm water(which produces the rise in radiance observed beyond 4 microns). Super-imposedover these two essentially graybody curves is the effect of atmospheric absorption inthe shorter wavelengths and atmospheric emission at the longer wavelength end.

A second scan was made approximately one degree to the right of the lake,producing the spectral signature shown as plot number 2. There is a notable decreaseof radiance at the short wavelength end of the second plot which has caused a factor-of-four reduction in the ordinate scale. At the longer wavelengths, both curvesapproximate a 3000K characteristic vAth superimposed effects of the interveningatmosphere.

g 4-1

Of particular importance to a contrast type seeker system is the spectral dif-ferenec between the two plots discussed above. This difference is included in site 25and labeled plot 1 - plot 2. Because of the large difference which typically exists atthe shorter wavelengths from 2 to 2. 6 microns, the difference plots were initiated at2. 6 microns to preclude a high ordinate scale. The difference plot is predominatedby the solar reflection from the lake iii the 3 to 4 micron region. Beyond 4 micronsthe radiance difference drops significantly due to the similarity in the radiating tem-perature of the two areas and the similarity in the atmospheric effects over theapproximately equivalent pathlengths. The rather wide CO 2 absorption band existingfrom 4. 1 to about 4. 6 microns is also indicative of the long pathlength to the lake(approximately 25 miles).

Site nmnber 8 (Figure 4-8) consists of spectral plots from four adjacent back-ground areas and the six difference plots resulting from the subtracted pairs. Thefirst two plots are of blue sky taken above Mt. Pinion. These two plots indicateradiance from scattered solar radiation in the 2.0 to 2.8-micron region and then thepresence of self-emission and atmospheric effects beyond 2. 8 microns to the end ofthe plot at 5. 4 microns. The rather broad "bump" existing at 4. 5 microns is due tothe warmer atmospheric CO 2 close to the measurement site. The structure fromabout 5 microns on is predominately H2 0 emission of .he atmosphere. The differenceplots for these two areas (plot number 1 - plot numbe': 2) indicates an almost neg-ligible contrast between the two. This difference plot is essentially the result ofinstrwument noise in the shorter wavelengths and the slight differences in indicatedtemperatures at the longer wavelengths. (A temperature change of 10 C for a 3001Kblackbody will produce a difference of about 4 microwatts per square centimeter-steradian - micron at 4 microns). Since the above plot shows a difference of lessthan 2 microwatts per square centimeter - steradian - micron at 4 microns, thedifference is probably due to the slight change in effective temperature (approximately0. 5° C) over the different measurement paths or due to a temperature change whichcould have taken place during the two minute interval in which the two measurementstook place.

Plots number 3 and 4 show spectra of sunlit snow and bare ground. The bareground was warmer than the snow as evidenced by the thermal image and the higherradiance of plot number 4 in the 4.5 to 5.4-micron region (note the ordinate scalechange). It is also interesting to note that the atmospheric structure in this sameregion of plot number 4 in phase reversed 180 degrees from that of the other threeplots, indicating that the C02 and H20 bands are absorbing the emitted radiation fromthe warmer ground. This phase reversal, which can best be examined by physicallyover-laying the two spectra, provides a good indication of the nature of the backgroundradiance when comparing various sites.

The difference spectra involving plot number 4 appear similar to one another dueto the relatively large radiance level of this particular plot which dominates the sub-traction. The difference levels for these plots are negative due to the sign conventionused in the subtraction. In addition, the C02 absorption band at 4. 5 microns is notas wide as was noted for the difference plot involving the sunlit lake of site 25(Figure 4-25). This is the result of the closer proximity of site 8.

Site number 6 (Figure 4-6) shows an interesting difference in the spectral ra-

diance of blue sky which was taken at two different elevation angles. The spectral

4-2..c . ' " "

1 radiance at 3 degree elevation shows a large amount of scattered sunlight in the2 to 2. 5-micron region and the effects of transversing a long horizontal pathlength ofessentially 300°K atmosphere. The spectral signature made at the higher 44 degreeelevation angle is dominated by atmospheric molecular emission of warm CO 2 and1120. The scattered solar radiation and atmospheric graybody continuum is to sucha low level that H20 molecular line emission can be seen in the 3.2 to 3.5-micronregion. The predominate H20 emission is at the longer wavelength end of the spectrumbetween 4.7 to 5. 4 microns, The radiance level of the dense CO 2 at 4. 4 microns is

I fairly independent of elevation angle.An anomaly that is present in most of the IR background spectral data is the small

double dip of CO 2 absorption centered at 4. 25 microns. The spectral plots presentedare referenced to essentially absolute zero by comparing each background to a fullfield blackbody at the temperature of liquid nitrogen. In physically performing theliquid nitrogen measurement, the small amount of residual CO 2 that is within the

1 instrument produces a small amount of absorption at 4.25 microns that is carriedthrough to the reduced plots. This absorption does not appear in the difference plots,however, since it is automatically eliminated during the subtraction process.

4KlI

iii

4-3

INFRARED BACKGROUND SITL NO. 1

LOCATION: BLUE RIDGEDATE! JUNE 15, 190PTIME: 1334PSTELEVATION: 7386 FTTEMPERATURE: 63

0F

RELATIVE HUMIDITY: 37%,SUN ANGLE: 640 EL 2300 AZ MAG

PLOT NO. 1

PLOT NO, 1: BRIGHiTCLOUDEL ANGLE; 24") AZ ANGLE: 3100 MAG

PLOT NO. 2: BLUE SKYEL ANGLE: 24.50 AZ ANGLE: 309.50 MAG

PHOTOGRAPH 0.7 - 0.9 MICRONS THERMAL IMAGE 2-5 MICRONS

PLOT NO, 1 - BRIGHT CLOUD PLOT NO, 2 - BLUE SKY

3n

, , ,

M;,.•'% • "IC'R0;i WAVELLN~tmH 101 •I ONS I

INFRARED BACKGROUND SITE NO. IDIFFERENCE PLOT

PLOT NO, I PLOT NO, 2

4 0

S,, 3,04,5 ,

INFARE BACKGROUN D SITE Ns O1A63896-1D ERENCE O4-4 - F PLOTeNO,1 2

* ue.A. @ M'

I :.I•

I,-I,II

LOCATION: BLUE RIDGEDATE: JUNE 15,1970 PLOTN 120TIME: 1322 PSTELEVATION: 7386 FEETTEMPERATURE: 63 0 FRELATIVE HUMIDITY: 37%

SUN ANGLE: 670 EL 2280 AZ MAG

PLOT NO, 1: BRIGHT CLOUD EDGEELANGLE: 190 AZ ANGLE: 2350MAG *PLOT NO. 1¶ -,P-

PLOT NO, 2: BLUE SKYEL ANGLE: 200 AZ ANGLE: 235UMAG

0

PHOTOGRAPH 0,7 - 0.9 MICRONS THERMAL IMAGE 2 - 5 MICRONS

PLOT NO. 1 - BRIGHT CLOUD EDGE PLOT NO. 2 - BLUE SKY

50

:11

~ ~i~0

WAVELINOTH (MItCR0N8: WRVELNOrH MIClRONSI

INFRARED BACKGROUNDDIFFERENCE PLOTPLOT NO,1 - PLOT NO. 2

1 20

00

I ts

4" .- 5/4-

L~~ ~ * Ij

* i INFRARED BACKGROUND SITE NO. 3

U ,

I

LOCATION: BLUE RIDGE PLOT NO 2

DATE: JUNE 15, 1970 SI TIME: 1358 PST

I ELEVATION: 7386 FEETTEMPERATURE: 630 FRELATIVE HUMIDITY: 35%SUN ANGLE: 570 EL 2350AZ MAG

PLOT NOl: BRIGHT CLOUDEL ANGLEi 200 AZ ANGLE: 3400 MAG 0 S

PLOT NO. 2: BLUE SKYELANGLE: 219 AZANGLE: 3400 MAG PL NO. 10

~10

PHOTOGRAPH 0.7 - 0.9 MICRONS THERMAL IMAGE 2 - 5 MICRONS

4PLOT NO. 1 - BRIGHT CLOUD PLOT NO,2- BLUE SKY

IsI' . w lU

II O

WARVILNOtH IMICIWH0 IANVELENUIH I MIC(RON3

INFRARED BACKGROUND SITE NO. 3DNI" ~DIFFERENCE PLOT

,. PLOT NO, I PLOT NO. 2

*U~tNUtNAlL flVNA&Mi

S4U I

U;",i 80

U,

40

'I'a - . .

A 63897-1 W VELEONOT I 11CR N51

S•0... .. 4 4-7

i1

INFRARED BACKGROUND SITE NO. 4

* LOCATION: BLUE RIDGEDATE; JUNE 15, 1970TIMEt 1406 PSTELEVATION: 7386 rEETTEMPERATURE: 62 0 FRELATI'VE HUMIDITY: 34%SUN ANGLE; 540 EL 2360 AZ MAG PLOT NO.1.2

PLOT NO. 1: BRIGHT CLOUDEL ANGLE: 100 AZ ANGLE 1300 MAG0

PLOT NO, 2: DARK CLOUDEL ANGLE: 90 AZ ANGLE: 1300 MAG

PLOT NO, 3: BLUE SKY X .. T No.ELANGLE: 110 AZANGLE: 1300 MAG P.* LOT NO,2

PHOTOGRAPH 0,7 - 0,9 MICRONS THERMAL IMAGE 2 - 5 MICRONS

PLOT NO, 1 - BRIGHT CLOUD PLOT NO,2 - DARK CLOUD

* 4

S I230*

C', .a

VQ 400

D 4 0 u

.. 0 ... .. ..

42 3 4WAVELENUGTH MIICRON01 WAVELtNOtH MICIRONS)

PLOT NO.3 - BLUE SKY

:50

3 4 5WAVELENGTH (MICRONS)

A63898,1

Figure 4-4.4-8. .

oC :' *' -, ,I C'

PLOT NO. 1 - PLOT NO. 2 PLOT No. I - PLOT NO. 3

40 .. . . . . . .• . . . . . . . . . . . z. . .. .. .. . .. . ..... . .. I--1

I

Lz

2 -0 '40

I

1, NR[I.ENrH (INFARDBAKROUNDSITENO.4VLFNH MEN

PLOTPO.O1-LOT.N.2 POTPNO1TPLOONO.

0200

~ 0

[ 0 1

31. 4.5 3.0 3.6 4.0 4.5 ,.0

WRVELENarH (MICROS) a MWVLLNOr I•Nf hRONS)

PLOT NO. 2 -PLOT NO. 3

A63899

zFigure 4-4 (Continued)

I 4-9

l ox

71

Ii

I'! FRARED BACKGROUND 31TE NO. 5

LOCATION: SAN ONO•-EDATE; APRUL. 28 1970TIME: W456PSTELEVATION: IoI0FEETrTE"IPERATURE: 64')F.SRELATIVE HUMIDITY: 32., PLOT NO..SUN ANGLE: 390 EL 'Q300 AZ MAG

,, PLOT NO 1: CLOUD6L ANGLE: 850AZ ANGLE: 240.)MAG PLOTNO. 1

PLOT NO. 2: JLUE SK'y ABOVE CLOLUD PLOT NO.3EL ANGLE: ') AZ ANGLE: 240 MAG " ""

PLOT NO,3: HILLSIDE - . ,EL ANGLE: 5' AZ ANGLE: 240 MAAG , ".E ANGLE: c.• .. ,

-. . - ,.- .

- , .,


PLOT NO, 1 - CLOUD PLOT NO, 2 - BLUE SKY ABOVE CLOUD

.' . . . . . . . . .

I Iii .

i '

, , [ I R O N I W -4 ,

PLOT NO, 3 - HILLSIDE

31 4 3Q

4 -10 Roo. , I t

Fig'u'e 4-3.

4-104

e l- 4 -. 7,z..

IINFRARED BACKGROUND SITE NO. 5DIFFERENCE PLOTS

I PLOT NO. 1 - PLOT NO. 2 PLOT NO. 1 - PLOT NO. 3

a -

,I 1, 1.5 4 4V, 5,0. - . .0 •5 .WAV ENGQN H IMICRON51 WAVfýFNO'I, IMIRON'Il

PLOT NO, 2 PLOT NO. 3

0 . .. . .

S0 .5 4'.0 4,•, 5.U"* ~W•V•{ No;H ! MICRUON5SA63889

Figure 4-5 (Continuerl..

I, A1

A8 88 f"$

INFRARED BACKGROUND SITE NO. 6IG TVERQVSII LOCATION: DESERT JjOT SPRINGS

DATE: APRIL 23, 1970-5TIME: 1237 PST

TMPEIIATIJRE: 760F PLOT NO. 22 '10REAIEHUMIDITY: 9%

SUN ANGLE: 65.70 EL 1920 AZ MAG

PLOT NO. 1: BLUE SKY 30EL ANGLE: 30 AZ ANGLE: 3450 MAG I w

PLOT NO, 2i HLUE SKY 440EL ANGLE: 440 AZ ANGLE: 3450 MAG ilillilf

PHOTOORAr .9 MICRONS THERMAL IMAGE 2-5 MICRONS

PLOT NO. I - BLUE SKY 3 0 PLOT NU.. 2 - LUE SKY 440

INFRARED BACKGROUND SITE NO. 6DIFFERENCE P'LOTPLOT Whu. 1 - PLOT NO. 2

IdIAWAVELENOT H :1cthIC a)

A63906-1I

4-12

I F INFRARED BACKGROUND SITE NO. 7

LOCATION: BLUE RIDGE, CALIF. PLOT NCJ,DATE: JAN 249, 1970

TIME: 12:21 PST 10I ELEVATION: 7386 FEETU TEMPERATURE: 49 0F______________

RELATIVE HUMIDITY: 13% - 200SUN ANGLE: 380 EL, 1700 AZ MAGcIPL-

* PLOT NO, 1; BLUE SKY* EL ANGLE: 120 AZ ANGLE: 2200 MAG 0,00

PLOT NO. 2: BLUE SKY* EL ANGLE: 120 AZ ANGLE: 220.60 MAGj ~

.0 .2 4PHOTOGRAPH 0.7 -0.9 MICRONS THERMAL IMAGE 2 -5 MICRONS

IPLOT NO.1- BLUE SKY PLOT NO. 2 -BLUE SKY

1 .~200

IIInr

J4 4

WAVELLNUM IH ~I N045 AVLNJmIMCiUS

INFRARED BACKGROUND SITE NO. 7DIFFERENCE PLOT

PLOT NO.1 -PLOT NO. 2

A63055-1 3.0 3.5 WPVELENOT 4H U(I~CRONSI , .

Figure 4-7.4 -1,3

.1 . .....~iZ~?Ii7Zi7ZZI._0A

INFRARED BACKGROUND SITE NO, 8

LOCATION: BLUE RIDGE, CALIF.DATE: JAN 29, 1970TIME: 11:32 PST 5ELEVATION: 7386 FEETTEMPERATURE: 49°FRELATIVE HUMIDITYA 12%SUN ANGLE: 370 EL. 1550 AZ MAG P2

PLOT NO, 1: BLUE SKY ABOVE MT. PINIONPL20

EL ANGLE: 90 AZ ANGLE: 2300 MAG

PLOT NO. 2: BLUE SKY ABOVE MT. PINION •r " l ' •€,EL ANGLE: 8,5° AZ ANGtE: 2300 MAG Q ,,LO NO.

PLOT NO. 3: SNOW COVERED PFAK 5- : €,! 'EL ANGLE: 80 AZ ANGLE: 2300 MAG ,20N100q

PLOT NO. 4: BARE GROUND 41, )EL ANGLE: 80 AZ ANGLE: 229,50 MAG


PLOT NO. 1 - BLUE SKY ABOVE MT. PINION PLOT NO. 3 - SNOW COVERED PEAK

200 1

:oO/ ... *

2'4 5 2 4 5WRVELENOTH UiICRONSI WAVELENOTH IMICRON5S

PLOT NO. 2 -BLUE SKY ABOVE MT. PINION PLOT NO, 4 -BARE GROUND

!5 20 a:200

ici

L 1 800 I

-o • 40

5 E

WRVELENOTH (MICRONS) N I0

A63051-1A

Figure 4-8.4-14

- .. . , -I -. ý O N-,

| DIFFERENCE PLOTS OF IR BACKGROUND SITE NO. 8PLOT NO. 1 -PLOT NO. 2 PLOT NO. 2- PLOT NO.3

I -a

-0

0-4 ,_ . AA ....• o . ...... L.... U. *-t-.-J."-" .- t4.&.4.. '.L....&...&..&...d. •.L ..M .. LL." ,o .. . . , .. ...&. . .. ....

3.0 ,,0 4,5E,0 4.,04. 6 4.5 5.0

PLOT NO. 1- PLOT NO. 3 PLOT NO. 2 - PLOT NO. 4

-00

S4

:1i

Uw w 200

40,, , t,', "' _i u,• 4:• . a. .. s.a,. ! ,.a.a . , LL,.a• .A . , ,u "..&ta.~ 4.. . .u..h..wU ...... .... ..... a... .. .. . . .A ~.1... &..4J.t

aL ...... L

3.0 3.5 .0 46 6.50 3035404WRVELEN~t'H I MICRONS I WAVELLNUrM (MICRONS!

PLOT NO.1I- PLOT NO. 4 PLOT NO. 3 -PLOT NO. 4

U 00

~. 0' - .

L.... z. . . . .20-...X.~...A.JA. At.l±LIi f~. .LIL.&J..4J44 I J4[ wO6- 7 AE~0i MCOS 8(o .IRE~0i IIRNI41

_ _ __loo-_ _ _ _

cc.k c : :.'r. ~ *~ £~ K~*.


LOCATION: BLUE RIDGE, CALIF.DATE: JAN 29, 1970TIME: 11:54 PSTELEVATION, 7386 FEET PLOT NO. 1TEMPERATURE: 49 °F S..,

RELATIVE HUMIDITY: 12%SUN ANGLE: 380 EL, 1620 AZ MAG PLOT NO. 2

P'LOT NO. 1: CLOUD COVER OVER MT, BALDYEL ANGLE: 7.0° AZ ANGLE: 138 0 MAG ...LOT.NO. . 200

PLOT NO, 2: CLOUD COVEREL ANGLE: 6,20 AZ ANGLE: 1380 MA PLOT NO4

P'..OT NO, 3- BLUE SKYEL ANGLE: 5,50 AZ ANGLE: 1380 MAG

PLOT NO.4: SNOW & ROCK PL NEL ANGLE: 5,30 AZ ANGLE: 1380 MAO

PLOT NO, 5: SNOW PATCHEL ANGLE: 4.70 AZ ANGLE: 1380 MAG


PLCT NO. I - CLOUD COVER OVER MT. BALDY PLOT NO. 3 - BLUE SKY

*2000 z

oo4

,400

S• 4oo4

-,•'zr rr t TL . t.,_. o L,...,&÷.•..a.,~ ,. .••••LLL.t,' •:.l. aa-,.-.,L -• A A•...a•..a J

2 3 - 4 2 AVELENOTH IMICROSWRVELEN0rtH MICRONS) RUNSI

PLOT NO, 2 - CLOU) COVER PLOT NO. 4 - SNOW & ROCK

SOMONAL.~'V~A : uUM=JAL VAM

or

400

a a~ 300

I,

200

a: 2 a:42WAV.E4 rHi 'MICRONS) S IqVELEN01H CRONSi

A63053-1 Figure 4-9.

4-16

?j I INFRARED BACKGROUND SiTE NO. 9

PLOT NO. 5 - SNOW PATCH

Sao

• •,'" •,.. 400

300

200

I ,I ]5 ~WRVELENgTH ( MICRONS)

I INFRARED BACKGROUND SITE NO. 9DIFFERENCE PLOTS

SPLOT NO. 1 - PLOT NO. 2 PLOT NO. 1 - PLOT NO. 440 -

-

z 10 a20

w wo

a 0

1 3.0 3.5 4.0 4.6 5.0 W3,0 3,4.0 4-5 5.0WRVELENGTH IMICRONS) WAVELENGTH (MICRONS)

PLOT NO. 1 -PLOT NO. 3 PLOT NO. 1- PLOT NO. 5

Go DVNA310

-z 4

a20 A

: 40~ 3. .0 .

WAVELENGTH (MICRONS) WAVELE.NGTH (MICRONS)A63100 Figure 4-9 (Continued).

4-17

e J

INFRARED BACKGROUND SITE NO. 9DIFFERENCE PLOTS

PLOT NO. 2 - PLOT NO. 3 PLOT NO. 3 - PLOT NO, 4

~ 0

30 hii

CIOl

- "°So•

t.J

0: &. ]i LJ..X ..tL..--L.L.J.....&.J-LJ..&..- .. , aa •. '!..,-.--.L.

3,0 3.5 4.0 4.5 5.0 3.0 3.5 4.0 4.5 5.0NRVELENGTH ( MICRONU WAVELENOGTH IMICRONSl )

PLOT NO. 2 -PLOT NO. 4 PLOT NO. 3 -PLOT NO. 5

2 0

zi

w 20

U

• : 4 0 . . . . . . ..

•. .. . . . . . .!•.• - - ,- .. . • • .3,0 3.5 4.0 4.5 5.0 30 3.5 4 4 5 5.0

WAVELENGTH (MICRONS) WNRVELENOTHI (MICRON$)

PLOT NO. 2 -PLOT NO. 5 PLOT NO. 4 - PLOT NO. 5

20I

0 ~Uw

15

,0 35 40 4..5 5, = ,0 3.0 4.0 4,5b.W•RVELEN0TN (MICiRONS) W RVELENOTrH ( MICRONS )A63054 Figure 4-9 (Continued).4-18

40HU *

f'1

INFRARED BACKGROUND SITE NO. 10I 'LOCATION: DESERT HOT SPRINGSDATE! APRIL 23, 1970TIME: 1154PSTELEVATION: 1087 FEETTEMPERATURE: 760FRELATIVE HUMIDITY: 9%SUN ANGLE: 68 0 EL 168 AZ MAG

POT NO, 1I , • . .

PLOT NO, 1: DISTANT HILLEL ANGLE: 2.20 AZ ANGLE: 2850 MAG

PLOT NO. 2: HOT HILLEL ANGLE: 1,8 0 AZ ANGLE: 285° MAG PLOT NO.2 i '


PLOT NO. 1- DISTANT HILL PLOT NO. 2 - HOT HILL-••~ ~ ~~ ~a -----

• -- r-• t

303I B K O D I N.gU

3 2 3WAVELENG'TH IMIC((RONS) W NVELENOTI, I't (CRONS

SINFRARED BACKGROUND SITE NO. 10"DIFFERENCE PLOTPLOT NO. 1 - PLOT NO. 2

tor

a .30

-. 0

5

f- -40

3.0 .35 4.0 4.5 5,0WRVELENCTH (M ICRONS)

A638921 Figure 4-10.

_ __4 -19_ _,


tG ''N

LOCATION: DESERT HOT SPRINGSDATE: APRIL 23,1970TIME: 1145 PSTELEVATION: 1087 FEETTEMPERATURE: 760FRELATIVE HUMIDITY: 9% PLOT NO. ISUN ANGLE: 680 EL 1620 AZ MA"

PLOT NO. 1: BLUE SKY PO oEL ANGLE: 5.2 AZ ANGLE: 2850 MAG

PLOT NO, 2: SNOW ON SAN GORGONIO PLOT N'3 10

EL ANGLE: 4,80 AZ ANGLE: 2850 MAG

PLOT NO, 3: SECOND MT, PEAK 2EL ANaLE: 3.0OAZANGLE: 285oMAG

PHOTOGRAPH 0,7 - 0.9 MICRONS THERMAL IMAGE 2-5 MICRONS

PLOT NO, I - BLUE SKY PLOT NO, 2 - SNOW ON SAN GORGONIO

S300

L 60 -•o

4020

w

_=2U

0 |00

42 3 4WAVELENOrO (MICRON) 58 3CON

PLOT No.3 - SECOND MT. PEAK

3 00

S200

• .............

WAVELENOTH (WIRONS)

A63893-1

4-20 Figure 4-11.

- $

r,-

--- .w =- --. . - -

't !Iý

,I.i

INFRARED BACKGROUND SITE NO. 11DIFFERENCE PLOTS


V) IQ•- o o -20

PLOT NO. 2-PLOT NO. 3

1, 25•

I ::

3.0 3,5 4.0 4.5 50OwAVCL-NNrr1 (/IICRONS )

"- A63894 W

Figure 4-11 (Continued).

42

"" ~4-21

* 1


LOCATION: SAN MARC=S PASSDATE: MAY 18, 1970TIME: 16:22 PSTELEVATION: 1850 FEET 50-m

TEMPERATURE: 7303FRELATIVE HUMIDITY: 46%SUN ANGLE: 190 EL, 2420 AZ MAG o

EL AGLE:- AAIGL: 19,20MAO...IP.APLOT No. I* ,-PLOT NO. 1 LESY2

EL ANGLE: -2,0 AZ ANGLE: 179,50 MAG

PLOT NO. 3: SU BNLI ROCKO.2 waEL ANGLE: -. 40 AZ ANGLE. 180.0 MAO 4PLOTNO4w

PLOT~~LO NO, 4:GEN3OIGEL ANGLE: -3,0 AZ ANGLE: 180,0 MAO

PHOTOGRAPH 0,7 -0.9 MICRONS THERMAL IMAGE 2-5 MICRONS

PLOT NOI- BLUE SKY PLOT NO. 3-SUNLIT ROCK

~0300

~200v,100

X- IcWAVELCN0?H (MIICRONS) WA IfVELENGTH U11Cft0N31

PLOT NO,.2 -FOG BANK PLOT No, 4-GREEN FOLIAGE

0 400

2N 0

Nz cc~j~

4-22

I INFRARED BACKGROUND SITE NO. 12

DIFFERENCE PLOTS jPLOT NO. 1- PLOT NO. 2 PLOT NO. 2 - PLOT NO, 3

60

IN I I 1

PLO NO LTN.3POTN,2-PO O

I a

:' ::

WARVh'.f'• H 'tIMICRON51 WPVE- E4O004 IM't(RON5 I

I

4PLOT NO. I PLO NO. 4 PLOT NO. 3 PLOT NO. 4

iiiI

oci: f:r t41 'mRO$ I M:

I

3-. 0 .4' , • b w, =l , . v5 r ,0

£ . 0

I A63940 lFigunre 4-12 (ContJinued).14

4-23

PLOT NO. -1

-LPLOTNO. 4

PLO NO3POTN.

INFRARED BACKGROUND SITE NO. 13AC;A HEMVSIO

LOCATION: SAN ONOFRE 5DATE: MAY 14, 1970TIME: 15:59 PSTELEVATION: 110 FEET ELTNEPH I 10TEMPERATURE: 720FF6%_

SUN ANGLE: 250 EL 2400 AZ MAG-

PLOT NO,.1: SROWN DIRT 'dPO

PLOT NO. 2: GREEN BUSH OF*~&

EL ANGLE.- +90 AZ ANGLE; 250 MAG

PLOT NO, 3: BLUE SKY i .~ PLOTNO. r;---EL ANGLE., +9.40 AZ ANGLE: 24.50 MAG .,,

PHOTOGRAPH 0,7 -0.9 MICRONS THERMAL IMAGE 2-5 MICRONS

PLOT NO.1- BROWN DIRT PLOT NO. 2-GREEN BUSH

. "RL zPA

E0B00

ago

."20

Nj 4zz

WRYEL9NOTH (IIICRON3) WRVELENOrH (MfICRONS8)

PLOT NO. 3 -BLUE SKY -

L200

3 4 5

WAVELENOTH (MICRONS I

A63972-14-24 Figure 4-13.

INFRARED BACKGROUND SITE NO. 13I DIFFERENCE PLOTS

IPLOT NO.1- PLOT NO. 2 PLOT NO.1- PLOT NO. 3

1 160

ow 20 j 40 1

.0 3. 4.0O 4. 5.0 3.0 3.5 4.0 4.5 .WRVELLEN0T (IMICRONSI WRVELEN0?8 (MIICRONS)

PLOT NO. 2 -PLOT NO. 3I _0

c NA -_

~iI ~ w

* ~WAVELCNOTiI (MIICRONS)

A63973


4-25

~ 1 INFRARED' BACKGROUND SITE NO. 14

LOCATION: DESERT HOTSPRINGSDATE: APRI1L 23, 1970ELEVATION: 1087 FEETTEMPERATURE: 76OF PO ORELATIVE HUMIDITY: 9%SUN ANGLL; 67,60 EL 1760 AZ MAG

PLOT NO. 2

PLOT NO. 1: BLUE SKYEL ANGLE: 8.50 AZ ANGLE: 2100 MAG

PLOT NO. 2: SNOW AND ROCKS PLOT N0EL ANGLE: 8.20 AZ ANGc.E; 2100 MAG

PLOT NO. 3: HOT SPOT BELOW PEAK iEL ANGLE: 7.00 AZ ANGLE: 2100 MAG


PLOT NO. 1 - BLUE SKY PLOT NO. 2 - SNOW AND ROCKS

3Z 00

7 44WAVELENGTH (MICRONS) W AVELENOTH (MI)CRUNSI

PLOT NO. 3 - HOT SPOTr BELOW PEAK

uo0

2100

WAVELE~NGTH (MICRONS)

A63890-1

Figvre 4-14.4-26

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _-_ _ _ _ - - - 7 -. ~7

~ 'A _


3 DIFFERENCE PLOTS


0 0

-0

-. 40

- 3 -60

.... . ... .. cc

0 .5 4 ,0 4.s 5,0 4 4,WRVELENOTH (I,11"CRON5 PLO TELENOTW ICRONS 1

PLOT NO. 2- PLOT NO. 3

'I --

-. • A63891

Figure 4-14 (Continued).4 i ,.

!i "" ~ 4-27 ,

1 70


LOCATION: BLUE RIDGE, CALIF.DATE: JAN 29, 1970TIME: 12:37 PSTELEVATION: 7386 FEETTEMPERATURE: 49 0 FRELATIVE HUMIDITY: 13% EI ISUN ANGLE: 37.50 EL, 1740 AZ MAG

PLOT NO, 1: TREE TRUNKEL ANGLE: 60 AZ ANGLE: 600 MAG • '," =°'• '..-'

jPLOT NO. 3PLOT NO. 2: PINE TREE 5 200EL ANGLE: 60 AZ ANGLE. 610 MAG -

PLOT NO. 3: BRUSH 500EL ANGLE: 60 AZ ANGLE, 620 MAG • ' -

PLOT NO. 4M ROCK PL OT N O NCEL ANGLE: 60 AZ ANGLE: 630 MAU PLOT NO 2 .- *

PLOT IN. I


PLOT NO. 1 - TREE TRUNK PLOT NO. 3 - BRUSH

100 4500

12000 -

a800 U300

200

400

WVELENTH (M MICRNS WVELN0tH ONS

PLOT NO-2- PINE TREE PLOT NO.4- ROCK

-' ________ '__ " - ___"__,__ ."

...

S160 800

S80w40

WAVELENGT5.(MICRONS) WAVELENGTH M ICO

pl IINFRARED BACKGROUND SITE NO. 15DIFFERENCE PLOTS

PLOT NO. - PLOT NO. 2 . PLOT NO. 2 - PLOT NO. 3

0 1

a0 E 40- "3 3.5 4,0 ,S 11. 3.0 ,.0 4.5 a

WAVELENGTH (MMICRONSI WAVELENGTH MIICRONS)

PLOT NO.1 -PLOT NO. 3 - PLOT NO. 2 -PLOT NO. 4

3. 304 4~

S3.0 A, .0 4.0 5.0 3.0 3,.0 4 .0 4.5 ,0.

r to

WRVULEN0rH IMICRONS) NVLNT HLO•

[' - ~~~~PLOT NO. 1-PLTro4 POTN,3- PLOT NO, 4

3.0 4.0 4.0 0 .0 3.o0 3.6 4,0 4.0 0.0

• . "i4MVELCNOWH M/ICRONS) WRVELLN0TM (MICRONS)r

,ii Figure 4-!5 (Continued).

I4g2.

_ z .200

KINFRARED BACKGROUND SITE NO. 16

LOCATION: SAN MARCOS PASSDATE: MAY 18, 1970TIME: 16:03 PSTELEVATION: 1850 FEETTEMPERATURE: 730 FvRELATIVE HUMIDITY: 46% 210SUN ANGLE: 240 EL 2400 AZ MAG i

PLOT NO.1~

PLOT NO, 1: BROWN SPOTEL ANGLE: ..120 AZ ANGLE: 1600 MAG

~ LOT NO.. ~PLOT NO, 2: SUNLIT ROCKEL ANGLE: -130 AZ ANGLE: 1610 MAG

PLOT NO. 3: SHADOW OF ROCK PLOT NO. 3EL ANGLE: 13.20AZ ANGLE: 1610 MAG . o


PLOT NO.1I- BROWN SPOT PLOT NO. 2 -SUNLIT ROCK

z, -500-

ou j

tE 2o

1400

24 3. IPLOT NO 3400AWO RC

0 240

2 3(4WAVEL ~ ~ ~ ~ ~WNELEOH IMICICRONLS)rj(iI~tO~

4-30

I1

' IINFRARED BACKGROUND SITE NO. 16

I DIFFERENCE PLOTSPLOT NO. 1- PLOT NO. 2 PLOT NO.1 - PLOT NO.3 3

"I °dA Oi M '' +'

; Z;a I

I '~*LOT NO. 2 - PLOT NO. 3

F7l

460

rC I, 4,C 4.• S-0

A63942 ,•" t.NGTHM` CRON .


4-31i+ 1:


0A

LOCATION: DESERT HOT SPRINGSDATE: APRIL23,1970TIME: 1222 PSTELEVATION: 40F7 FEET PLOT NO.2*TEMPERATURE: 760F ..RELATIVE HUMIDITY: 9% ,SUN ANGLE: 66,80 EL 1840 AZ MAG

PLOT NO, 1: NEAR DESERT SAND - ,EL ANGLE: -. 60 AZANGLE: 3000 MAG

PLOT NO. 1PLOT NO, 2: NEAR DESERT SAGE BRUSHEL ANGLE: -. 60 AZ ANGLE: 3010 MA"-


PLOT NO, 1 - NEAR DESERT SAND PLOT NO. 2 - NEAR DESERT SAGE BRUSH

'200

F--1

w .

0 .L .. . . .&s..... J. t..L ... . .4 . ..234I 3 4 8

WAVELEN~rH (MICRONS) WRVELENUTH (MICRONSI

INFRARED BACKGROUND SITE NO. 17DIFFERENCE PLOT

20PLOT NO, 1 - PLOT NO. 2

gloo

r

3.0 385 4,0 4.,8 5,0A63905-1

WFVEL END tH (I|CRONS):

Figure 4-17.

4-32

_ _ ,L,

•.• , • • , ~ ~ ~~~~. . 1.,•,, .. .. ,•, .a

r!

INFRARED BACKGROUND SITE NO. 18' ILOCATION: SAN ONOFREDATE: MAY 14, 1970TIME: 15:45 PSTELEVATION! 110 FEET

2 100

TEMPERATURE: 720 F -,.

RELATIVE HUMIDITY: 80% , ''

SUN ANGLE: 270 EL 2400 AZ MAG PLOT NO 2

~PLOT NO, 2•_ ••'".

POT NO, 1: BRIGHT DIRT 10 " "

EL ANGLE: 60 AZ ANGLE: 3200 MAG

PLOT NO. 2; GREEN BUSHj.EL ANGLE: 6.20 AZ ANGLE: 3200 MAG


"PLOT NO. 1 - BRIGHT DIRT PLOT NO, 2 - GREEN BUSH

R0 UNORAL OYNAAMSP- *UA VA~

200

404

w w

lw 300

a IOU

31523I C4 5

•4. IWAVELENGTH (MICRONS) WAVELENGTH IIICRON$)


DIFFERENCE PLOT

PLOT NO, 1 PLOT NO. 2

140

o

Itf I

•' =3.0 3;, 4.b 4,5 5.0WAVELENG•TH IMIlCRONS)

A63978-1Figure 4-18-S~4-33

Ijii?

__ _ _ _ _ __m


LOCATION: SAN ONOFREDATE: MAY 14, 1970 .TIME: 14:59 PSTELEVATION: 110 FEETTEMPERATURE: 72°F PLOT NO. 1 -. __ * I.RELATIVE HUMIDITY: 60%SUN ANGLE: 39,50 EL 2360 AZ MAU

PLOT NO, .1: BLUE SKYEL ANGLE: +.50 AZ ANGLE: 2170 MAG

PLOT NO. 2: WATEREL ANGLE: 50 AZ ANGLE: 2170 MAG PLOT O.

PLOT No, 3: BUSHEL ANGLE. -10 AZ ANGLE. 2170 MAG

PHOTOGRAPH 0.7 - 0,9 MICRONS THERMAL IMAGE 2-5 MICRONS

PLOT NO, 1 - BLUE SKY PLOT NO. 2 - WATER

0.. A ewyNNL•jm_ UNAA500. V

EI- 40

Scl00

N N

6200

2 90

E Co

o 0

PLOT NO. 3 - BUSH

-300

200

(0N. 40

aAEE~H MCOS

A63976-Fiue -9

4-34


PLOT NO,1 I PLOT NO. 2 DIFRNEPOS PLOT NO.1- PLOT NO. 3

I a i0

PLOT NO. 2 -PLOT NO,.3

20 a

izir


4-35


LOCATION: SAN ONOFREDATE: APRIL28, 1970TIME: 1515PSTELEVATION: 110FFETTEMPERATURE: 62 FRELATIVE HUMPITY: 3g% 20SUN ANGLE: 34 EL 232 AZ MAG PLOT NO. I

PLOT NO, 1: CLOUD OVER OCEA,ý 5 2q.

EL ANGLE: +,6 AZANGLE: 195 MAG PLOTNO. 2

PLOT NO. 2: ABOVE OCEAN HORIZON NOTEL ANGLE; +,30 AZANGLE: 1950MAG

PLOT NO, 3: BELOW OCEAN HORIZONEL ANGLE: -. 3o AZANGLE: 1950 MAC


PLOT NO, 1 - CLOUD OVER OCEAN PLOT NO, 2 - ABOVE OCEAN HORIZON

10000

t - 400

4ooo

z U,

34 5 34

WAVMLEN0rH |MICRONS WRVELENj0H 1t:ICRONSI

PLOT NO. 3 - BELOW OCEAN HORIZON

8~0•

, U,

; •~ 100

2 3

A63884.1 WAVELEN0TH IMICRONS)

4-36 Figure 4-20.

_____ _____ _____-_,(A

,, ,- .............. ~ _ 4_ .....J:'V• .•:

niiINFRARED BACKGROUND SITE NO. 20I DIFFERENCE PLOTS

SI PLOT NO. I - PLOT NO. 2 PLOT NO. 1- PLOT NO. 3

; LotA t

l III I '

"I I 1 1.I 4, 0 4.5 500 3.0 5 4(1i

Y WELyN0r

i MIR QN3 id.v ' NQ H I ICRON5I

i PLOT NO 2 -PLOT NO, 3

130[ 4 L Y A

1'4

S0 '

I W0AVE 4. 34" 1 5r A63885 Vv NJTI 1IL,40HII

SFigure 4-20 (Continued).

I 4-

4-37

A~ i

'1

INFRARED BACKGROUND SITE NO. 21 -.A4

A H a

LOCATION: SAN ONOFREDATE: APRIL 28,1970TIME: 1528 PST ..

ELEVATION: 110FEET "TEMPERATURE: 600F 4PLoTNO 1RELATIVE HUMIDITY: 41%-, '".•eSUN ANGLE: 310 EL 2300 AZ MAG tA PLOT NO.2 2 ' .

PLOT NO, 1: CLOUD OVER CATALINA •'PLOT NO. 3EL ANGLE: +,5r AZ ANGLE: 2300 MAO I ..

PLOT NO. 2: CATALINA ISLAND ...EL ANGLE: +,2° AZ ANGLE: 2300 MAG

PLOT NO, 3: OCEAN BELOW CATALINAEL ANGLE: -. 3' AZ ANGLE: 230' MAO


PLOT NO. 1 - CLOUD OVER CATALINA PLOT NO. 2- CATALINA ISLAND

2 2

, •110600

4400 9

a:

SIz

2 4 5 2 3 4 .WAVELENGTH (MICRONS IWAV'LENOTI (MIICRONS)

PLOT NO. 3 -OCEAN BELOW CATALINA

ago

cc

3 4

Fiur 4-204-38

S~INFRARED BACKGROUND SITE NO. 21

S DIFERENCE PLOTS

PLOT NO. 1 - PLOT NO. 2 PLOT NO. 1 - PLOT NO. 3

it IH0

S3 10 M. . . 5 .0 1= .0 I S4 0 4 . 5 S .0

W AV f'" EN I• t H I II JC R O N ý . W A.5 M V LI rN ~ r H t f [ ( .R (] N Io

PPLOT NO, 2 -OPLOT NO. 3

I..Aa

I -10

A63887 PL FO 'NOTH 2-PL RONO.3


1~

4-39

. .....

AK

F"1


AG A. THRMOVSI.LOCATION: SAN ONOFREDAr-'. MAY 14, 1970TIME: 15i:11 PST 9ELEVATION', 110 FEETTEMPERATURE: 720FRELATIVE HUMIDITY: 6 LY%SUN ANGLE: 35.50 EL 2390 AZ MAG2 o

,ýLOT NO. 1: SURFI IeEL ANGLE: -90 AZ ANGLE: 2100 MAGPLTN.ION.3

PLOT NO. 2: SAND BEACHEL ANGLE: -100 AZ ANGLE: 2100~ MAG o5

PLor NO. 3: GREEN BRUSHEL ANGLE: -950AZ ANGLE: 2110MAG P LOT NO. 2~

20 10PLOT NO. 4: SUNLIT EDGE OF HILL PO OEL ANGLE: -100 AZ ANGLE: A120MAG

a~qjL TNOf


PLOT NO. 1- SURF PLOT NO, 3 -GREEN BUSH

300

)00E

WAVELENGTH (MIICRONS) WAVELENGTH IMIC RONS)

PLOT NO. 2 - SAN EC PLOT NO. 4 - SUNLIT EDGE OF HILL

r 200

S100

2l0O

2 3 4 02 3 4WAVELENOTH (MICRONS) WAVELENGTH IMICRONSI

A63g74-1 Fgr -2

4-40 r gr -2

_•iI

I iINFRARED BACKGROUND SITE NO. 22.1 (DIFFERENCE PLOTS

PLOT NO. 1 -PLOT NO. 2 PLOT NO. 2 -PLOT NO. 3

o30

~20

1 10S:- 3.0 34 . RV-LENnT4 (tICRONS .0

;-30

PLOT NO. 1- PLOT NO. 3 PLOT NO. 2 - PLOT NO. 4

20 2

• N al|

200.0

3.0 .5 4.0 4. 5.0 a 3.0 3.5 4.0 4.5 5.0. WAVELENGTW (MIICRONS)w WAVELEN•TH I(MICRONS)

PLOT NO. 1- PLOT NO. 4 PLOT NO. 3 -PLOT NO. 4

-- *I.II

"L L -

20 1 .

4--'

0 ,

3 . .- . . . . . .3. 4.a. . . - . .

:6 9 5WVEENT MC ON1kIEE20OM[RN

a -404-4a


LOCATION: LAKE CASITASDATE: MAY 19, 1970TIME: 9:50 PSTELEVATION: 700 FEETTEMPERATURE: 68°FRELATIVE HUMIDITY: 56%SUN ANGLE: 580 EL 970 AZ MAG

. ~PLOT NO1

PLOT NO. 1: SUN GLINT OFF WATEREL ANGLE: -20 AZ ANGLE: 760 MAG

PLOT NO. 2: DARK SIDE OF ?PNINSULAEL ANGLE: -20 AZ ANGLE: 750 MAG

PLOT NO, 2PLOT NO. 3: CALM WATEREL ANGLE: -2.50AZ ANGLE: 750 MAG

PLOT NO. 3


PLOT NO. 1 - SUN GLINT OFF WATER PLOT NO. 2 - DARK SIDE OF PENINSULA

2~

Soo

~4OOU IOU

3 5 2 3

WRVELENOTH hI ClRONS; WRVELENOTH (IMICRON31

PLOT NO. 3 -CALM WATER

-3000_ _ _

IOU

C C

2 3 2 6

WAVELENGTH IIS|CRONr

A63944-1

Figure 4-23.4-42

I . , . : u:,t.,,.S•_PLOT NO.3,-CALM,, WATER

DIFFERENCE PLOTS

PLOT NO. I PLOT NO. 3 PLOT NO. I PLOT NO. 2

S2-0 -

5I

11

IQI0

PLOT NO. 2 - PLOT NO. 3

.ki

, A63945Figure 4-23 (Continued).

1 IT4-43 "

= : 1 P L O N O . , , . . 2 - P L O T N OL , 3/ ..X; •

, INFRARED BACKGROUND SITE NO. 24

LOCATION: LAKE CASITAS

DATE: MAY 19, 1970TIME: 10:15 PSTELEVATION: 700 FEETTEMPERATURE: 67OF PLUT NO.

RELATIVE HUMIDITY: 58% -* SUN ANGLE: 63 0 EL 1050 AZ MAG 2oI

PLOT NO, 1: DRY GRASS ON PENINSULA 10EL ANGLE: -90 AZ ANGLE: 830 MAG PLOT NO. 2

PLOT NO, 2: CALM WATERE.EL ANGLE: -100 AZ ANGLE: 820 MA2

iiPHOTOGRAPH 0.7 - 0.9 MICRONS THERMAL IMAGE 2 - 5 MICRONS

PLOT NO. I - DRY GRASS ON PENINSULA PLOT NO. 2 - CALM WATER

zoo ft atll200 Ph

G00

2000

i 4RVI•LEN~rN LIICR0M•I 0 wIVELgN~rH IlIICR0NSI

3 4 52 3 ,

INFRARED BACKGROUND SITE NO. 24DIFFERENCE PLOTPLOT NO. 1- PLOT NO. 2

- L

A63943-1

Figure 4-24.4-44

-~~~~~-. IF-.--- n w,-

?,omomm!


LOCATION: BLUE RIDGE, CALIF.DATE: JAN 29, 1970 ' PLOT NO. 1 PLOT NO. 2 .,•

ELEVATION- 7386 FEET ;Y.TEMPERATURE: 50OFRELATIVE HUMIDITY: 13,5%SUN ANL.350 EL, 1800 AZ MAGI IF" z,]I

PLOT NO. 1: SUN LIT LAKE a -k ., . , , 'EL ANGLE: -20 AZ ANGLE: 1750 MAG ts A. ..

PLOT NO. 2: RIGHT OF SUN LIT LAKE 3vEL ANGLE: -20 AZ ANGLE: 1760 MAG • .. "


PLOT NO. 1 - SUNLIT LAKE PLOT NO. 2 - RIGHT OF SUNLIT LAKE

a 2400~ 7 600

0c 400

•' INFRARED BACKGROUND SITE NO. 25

"= ~DIFFERENCE PLOT

•- ~PLOT NO. 1- PLOT NO. 2

S200

4',1

,,•-AVLEGT (MCOS WAVLEGT RUNS)•EO4.OfII•O S•4, .ý2j00.

A63059-1 W

"" .LFigure 4-25.

Ir•

SECTION 5

, •PHASE-Il UV MEASUREMENT DATA10.30-0.44u)

I.: Ii ' i1

: i A

• 9.

Section 5I PHASE-II UV MEASUREMENT DATA (0.30 - 0.44 A)

Figures 5-1 through 5-24 show the ultraviolet spectra of various natural back-grounds. Again, the near-IR photographs illustrate the spatial relationships be-tween the data plots. The UV photographs were taken with a boresighted camera toillustrate the intcgTated image which exists in the 350 to 400 millimicron region. Thevarious sites include and are arranged in the following approximate sequence; clouds,

£ sky, snow, terrain and water.

The spectrometer was calibrated at each measurement location with collimated,full-field xenon and mercury vapor sources to establish the radiance and wavelengthscales. The xenon source has also been referenced to an NBS traceable ribbonfilament tungsten lamp to establish absolute radiance levels.

The spectral data were taken over the range of 200 to 440 millimicrons; however,the shorter wavelength data was excluded from the final plots since the radiance levelsin the region were extremely low due to absorption by atmospheric ozone. The or-dinate scale values are selected by the computer program to fit the data between themaximum and minimum values. The UV data presented in this section represent asingle spectral scan which required about 20 seconds to cover the 300 to 440 millimi-

cron region.The UV spectral plots (see Figure 5-1 for example) generally show characteristics

of a rapid rise in radiance level over the wavelength region of 300 to 330 millimicronsfollowed by variations about a gradually increasing.average radiance value to the limitsI of the plot of 440 millimicrons. The actual peak in the radiance curve will generallyoccur at some wavelength beyond 440 millimicrons depending on the particular back-ground and measurement conditions.

The difference plots, again obtained by spectral subtraction, are less dramatic

than exhibited in the IR spectral region due to the lack of strong atmospheric absorp-tion bands or effects of self-emission of backgrounds in the UV region. In addition,most terrain features are very non-reflective in the UV region and any observed ra-diance is generally due to the same effects which give rise to sky radiance. Plotnumber 1 - plot number 2 of site number 1 is typical of cloud/sky backgroumds; thespectral difference produces a generally rising characteristic from 300 to 440 mil-limicrons.sFigure 5-17 shows spectra obtained from terrain (pine trees) and blue sky. There

is a striking similarity between the spectral shapes of these two plots. This spectralsimilarity is due to the spectrally flat, non-reflective nature of the terrain which alsogives rise to a reduced magnitude of the ordinate scale. The difference plot is quite"similar in spectral shape to that of the sky, and typical of most other difference plotsinvolving terrain backgrounds.

-- 5-1

' t :9

I. - -.

The differences that exist in blue sky radiance as a function of elevation angle aredemonstrated in Figure 5-12. Spectral measurements were made at three elevationA angles; 3 degrees, slightly above the horizon; at 44 degrees, in a portion of deep bluesky; and at 69 degrees elevation. The major difference between the 3 degree spectralplot and the daita taken at the higher elevation angles is a reduction in the longer wave-

* length radiance at the higher angles due to reduced Mie scattering. The radiance levelat 340 milliniicrons is reasonably constant at 0. 009 watts per square centi meter -ste radian-micron from 3 degree elevation up to at least 69 degrees (the limit of the UV instru-mnentation) for this particular site.

5-2

ULTRAVIOLET BACKGROUND SITE NO. 1LOCATION: BLUE RIDGE, CALIF PLOT NO. 1 - DEEP BLUE SKYDATE: MARCH 31, 1970TIME: 13108 PST EL ANGLE: 220 AZ ANGLE 950 MAGELEVATION: 7386 FEETTEMPERATIVE: 39°F PLOT NO. 2 - BRIGHT CLOUDRELATIVE HUMIDITY: 28%SUN ANGLE: 55) EL AV 195 MAG EL ANGLE: 210 AZ ANGLE 950 MAG

I "PLOT NO. I ." .

PLOT NO. 2.

IR PHOTOGRAPH .7 - .9 MICRONS UV PHOTOGRAPH .35 - .40 MICRONS

PLOT NO, 1 - DEEP BLUE SKY PLOT NO, 2 - BRIGHT CLOUD

-0.02

0.0001 .. . .. . . . 4 o. .... J'

o o, t

300 320 340 360 380 400 420 300 320 340 300 380 400 4204AVELENGTH M ILLI1ICRONS) WRVELENGTH IMILLIMICRON!0I

ULTRAVIOLET BACKGROUND SITE NO. 26DIFFERENCE PLOTPLOT NO. 2 - PLOT NO. I

.. . . . . ... . .. . .

M W

JOC4 361.• q• 400 42(',1~~v .14111 -MIl' !mICLR0OWI

A63445-1 Figutire 54-1. 5-3

ULTRAVIOLET BACKGROUND SITE NO. 2

LOCATION: BLUE RIDGE, CALIF PLOT NO, 1 - CLOUDDATE: MARCH 31, 1970TIME: 12:00 PST EL ANGLE: 17.50 AZ ANGLE: 95' MAG

ELEVATION: 7386 FEET PLOT NO. 2- BLUE SKYTEMPERATIVE: 360F

RELATIVE HUMIDITY: 37% EL ANGLE: 180 AZ ANGLE: 95 MAG

SUN ANGLE: 600 EL 1650 AZ

PLOT NO,2


PLOT NO. 1 - CLOUD PLOT NO. 2 - BLUE SKY

ý0024[

!0.0 ! -06

0.000',.......- . _ _0_000300 320 340 360 380 400 420 3LJ0 320 340 380 380 400 420

I4RVELLN0TX IIILLI I1CRONI) WA4VELENGTH (lHiLLIMICRONSI

ULTRAVIOLET BACKGROUND SITE NO. 27DIFFERENCE PLOTPLOT NO. 1 - PLOT NO, 2

LL

a 0.004•

13(0 320 340 360 380 400 420A,481WVELLNGTH 't4ILLIMICR0NSI

A63448-454 Figure 5-2.

____ ___ ___ ____ ___ ___ ____ ___ ___ ____ ___ ___ __

4'7'


i LOCATION: BLUE RIDGE PLOT NO. 1 - CLOUDDATE: MARCH,31, 1970TIME: 11:15 PST EL ANGLE: 110 AZ ANGLE: 120) MAGELEVATION: 7386 FEETTEMPERATURE: 360F PLOT NO, 2 - SKYRELATIVE HUMIDITY: 37%SUN ANGLE: 600 EL 1600 AZ (4AG EL ANGLE: 11.50 AZ ANGLE: 1190 MAG

PLOT NO. 1


PLOT NO. 1 - CLOUD PLOT NO. 2- SKY

- !r~ r- rS~0.02

0.00~~g .. .... .... .

300 320 340 360 360 400 420 300 320 340 360 380 400 420WAVELE•NTH I(IILLIMICRONS) WAVELtNOTH (NILLImICKONS)

ULTRAVIOLET BACKGROUND SITE NO. 28DIFFERENCE PLOT

PLOT NO. 1 -PLOT NO, 2

2 0006 1! -!

W O-.0.00 .... ..

300 320 340 360 360 400 420A677- WAMVELENGTH I MILL lACRONS !

A63777-1

I ~Figure 5-3.

ULTRAVIOLET BACKGROUND SITE NO. 4 ILOCATION: BLUE RIDGE PLOT NO. 1 - BRIGHT CLOUDDATE: MARCH 31, 1970TIME: 13:59 PST EL ANGLE: 150 AZ ANGLE: 2000 MAGELEVATION: 7386 FEETTEMPERATURE: 40OF PLOTNO. 2 -BLUESKYRELATIVE HUMIDITY: 26%SUN ANGLE: 470 EL 2090 AZ MAG EL ANGLE: 160 AZ ANGLE: 2000 MAG

PLT NO. 2 ,,, ',• °

-• •PLC)t NO. I


PLOT NO. 1 - BRIGHT CLOUD PLOT NO, 2 - BLUE SKY

........ ..

'.-.2 .•,i',.0,0" I .

Yor 2zo 340 30 300 400 422 3020 30 040 380 38 400 420

WAVELL804

4 IMILLI0I~80MSI 18VEL NoIr I MI8I0'0SI

ULTRAVIOLET BACKGROUND SITE NO. 29DIFFERENCE PLOTPLOT NO. 1 -PLOT NO. 2

0,020

0 d ,0 20 40 ?

A63776-1 30 'Wo20 30 80o 38L 0 400 42

5-6 Figure 5-4.

-I I ULTRAVIOLET BACKGROUND SITE NO. 5, LOCATION: BLUE RIDGE PLOT NO. 1 - BRIGHT CLOUD

DATE: MARCH 31, 1970TIME: 1405 PST EL ANGLE: 180 AZ ANGLE: 2000MAGELEVATION: 7386 FEETTEMPERATURE: 40°F PLOT NO. 2 - BLUE GKYRELATIVE HUMIDITY: 26%SUN ANGLE: 460 EL 2100 AZ MAG EL ANGLE: 18.50 AZ ANGLE: 1990 MAG

PO PNOT 2O •. •'

I NO I; >


PLOT NO, 1-BRIGHT CLOUD PLOT NO, 2-BLUE SKY

0.04

0ouo

°I:s

IOU~ 400 40020.... s•'•~.. no0 • 40 •0 00 4 4010 20 "40 36a 3 6 4 200•l. I•RW VEL[4N Ir H tlqLL I MI CRONS I WARVELLNOTH I MILL I PICRONS I

ULTRAVIOLET BACKGROUND SITE NO. 30"-, DIFFERENCE PLOT


0 .0 .. ... ....OC ,0t

JO 32i 340 380 300 400 420AVtLENJ THN IMILLifltCRONS•

A63775-1

Figure 5-5. I5-7

I *,... I.*•

V ULTRAVIOLET BACKGROUND SITE NO. 6LOCATION: B3LUE RIDGE, CALIF PLOT NO. 1 - BRIGHT CLOUDDATEi MAHCH 31, 197000TIME; 12:36 P'ST EL ANGLE: 110 AZ ANGLE! 165' MAGELEVAJ'ONi 7386 FF.ETTEMPERATIVE: 36 0F PLOT NO. 2 - BLUE SKYRELATIVE HUMIDITY: 371vSUN ANGLE: 58% EL 1820 AZ MAG; EL ANGLE: 120 AZ ANGLE: 1650 MAG

~.441

,,*-PLO NO.,;

IA PHOTOGRAPH .7 - .9 MICRONS UV PHOTOGRAPH .35 - .40 MICRONS

PLOT NO, 1 - BRIGHT CLOUD PLOT NO. 2 - BLUE SKYO-NOAL OCM14AAK

I.A 6I0 .0 . . .. .. .. .

"u 3 4 36 3 -u 4'030 30 3c 360 360 400 4 20WAVELENUT11 (MLLIMICRO~ti WVELENGTH (ILMCOS

ULTRAVIOLET BACKGROUND -SITE NO. 3.1DIFFERENCE PLOTPLOT NO. 1 PLOT NO. 2

0 .fuqC a

o o

1 4.0

S~~~~~~ 'i Ud .... '44",0 dV~kiC' ','I6)d

It

ULTRAVIOLET BACKGROUND SITE NO. 7LOCATION: POMONA, CALIF PLOT NO. 1 - BRIGHT CLOUD

DATE: MAY 6, 1970

TIME: 13153 PST EL ANGLE: 340 AZ ANGLE: 210P MAGU ELEVATION: 795 FEET

TEMPERATIVE: 68°F PLOT NO. 2 - BLUE SKYRELATIVE HUMIDITY: 34%SUN ANGLE: 55.50 EL 2230 EL MAG EL ANGLE: 35' AZ ANGLE: 2100 MAG

PLOT NO. 2

S I• ;° ,, . . .

PLOT NO, I

IR PHOTOGRAPH .7 .9 MICRONS UV PHOTOGRAPH .35 .40 MICRONS

PLOT NO. 1 BRIGHT CLOUD PLOT NO. 2 - BLUE SKY

', ,,-,'",,,.

0.0303

!t-0 0WAVELENGRH ,7- 9MICRONCS UV HOTGRAH IMIL.0MICRONS0

---

IJ ~~~~~~PLOT NO, I -- RGT LU PLOT NO. 2 -BU K

.............. ............. ... .J~ ............A- 340.0-

S '300Q 32•0 340 360 360 400 420 300 320 340 360O 360 400 420

ICAVtLENOrK OIILLIeIICRONSI kIRVLLAiNOTr1 IIILLIMICKNONJ


•] PLOT NO. 1 - PLOT NO, 2

0 C

AG3458-1

'IL

ULTRAVIOLET BACKGROUND SITE NO. 8LOCATION: POMONA, CALIF PLOT NO. 1 - BRIGHT CLOUDDATE: MAY 6. 1970TIME: 14:07 PST EL ANGLE: - 260AZ ANGLE: 2750 MACELEVATION: 795 FEETTEMPERATIVE: 68°F PLOT NO. 2 BLUE SKYRELATIVE HUMIDITY: 34%SUN ANGLE: 51.50 EL 2250 AZ MAG EL ANGLE: - 26°AZ ANGLE: 223°MAG

PLOT NON 21


PLOT NO. 1 - BRIGHT CLOUD PLOT NO. 2 - BLUE SKY

........ . . .. .. . . .0 0 . .. ...• ........3 ¢ ,'10 J " o 4 Z 30 0 3 2 0 3 4 0 .96 0 30 0 4 00 4 2 0koveif.W.'" ;0I1.t MIC;RONSI WAVELL N til I rMILLIMICREMN I


PLOT NO. 1 - PLOT NO, 2

IJ

A63457-1

3-.10 1"igurc 0-8.

ULTRAVIOLET BACKGROUND SITE NO. 9LOCATION: POMONA, CALIF PLOT NO. 1 - BRIGHT CLOUDDATE: MAY 6, 1970TIME: 4:13 PST EL ANGLE: 110 AZ ANGLE: 3200 MAGELEVATION: 795 FEETTEMPERATIVE: 680 F PLOT NO. 2 - DARK PART OF CLOUDRELATIVE HUMIDITY: 34%SUN ANGLE: 50 EL 2270a AZ MAG EL ANGLE: 120 AZ ANGLE: 3200 MAG

IR PHOTOGRAPH .7 -. 9 MICRONS UV PHOTOGRAPH .35 -. 40 MICRONS

PLOT NO. 1I SHIGHT CLOUD PLOT NO. 2 -DARK PART OF CLOUD

c ~ .008

0.004000

-~0 00004I

0 u 32 .... J..&.Ls.40 ... ii l ad..t I 400 420 300 320 340 300 380 '00 a1W14VELENOITH IMLIIRN IWAVELLNOTIM IILLIMjCIIUN8I

ULTRAVIOLET BACKGROUND SIThi NO. 34DIFFERENCE PLOTPLOT NO.1I-PLOT NO. 2

L .1

11140 910) J"ll) 400 4')

A03469-1 ~v 1"iguro 5-mllI.~R

UTA'VIOLET BACKGROUND SITE NO. 10 EG

LO A IN PM N .CL IF PLOT NO. 1 - CLOUD LE , 80EA

TIMEMONA CALIF P EL ANGLE - 150 AZ A G E 8 A

7I E 4'S S95 FEET PLOT NO.1 - LU K

ELEVATION. -8F

ELAN LE -T.~ A N L 1 A

TE!MPERATIVE' 68EL AN

RELATIVE U olY 34

40 E01 129CAZONS

PLOT

NON

11 ~ ~PLOT NO. 1 7 CLOUD ED)GE

'."

rF

Moou

ULTRVIOLT BCKGRUND ITENO. 35

DIF~ERNCE PLOT

IPLOT NOo.PPLOT ~ ~ ~ ......

.........

A6i3456-1

5)-I. 4

* ULTRAVIOLET BACKGROUND SITE NO. 11LOCATION: BLUE RIDGE, CALIF PLOT NO. 1 - SNOW COVERED MOUNTAINDATE: MARCH 31, 1970

(TIME: 12:25 PST EL ANGLE; 70 AZ ANGLE: 2220 MAGELEVATION: 7386 FEET

*TEMPERATIVE: 36OF PLOT NO. 2 - BLUE SKY* RELATIVE HUMIDITY: 37%

SUN ANGLE: 58.60 EL 1770 AZ MAG EL ANGLE: go AZ ANGLE-' 2220 MAG

'A'


PLOT NO. 1 - SNOW COVERED MOUNTAIN PLOT NO. 2 - BLUE SKY

ask"^.O 0)5~

0 .0c 0,005NT)

WAELNTH 1ILLIMI.LRON)S) A EO IILM RGS

ULTRAVIOLET BACKGROUND SITE NO. 36DIFFERENCE PLOTPLOT NO.1- PLOT NO. 2

0. 004

100 10 340 360( 1011 401 412UA63454-2 W)IVELEN0)H I MILLIMI(U00N5

1,'iguo 5-11


LOCATION: DESERT HOT SPRINGS PLOT NO. 1 - BLUE SKYDAlIE: APRIL 23, 1970 EL ANGLE: 30 AZ ANGLE: 3450 MAGTIME: 13:54PST PLOT NO. 2.-BLUE SKY

ELEVATION; 1087 FEET EL ANGLE: 440 AZ ANGLE: 3450 MAGTEMPERATURE: 790 F PLOTNO, 3-BLUESKYRELATIVE HUMIDITY: 8.5%SUN ANGLE: 53,60 EL 2180 AZ MAG EL ANGLE: 690 AZ ANGLE: 3450 MAO

SPLOTNO. 3

69 EL


PLOT NO. 1 - BLUE SKY PLOT NO, 2 - BLUE SKY.............. .... ...... .................... 'jjc-*'

2/2

*,, ', ... p1

I.A. VE 1,1\f "WK '•.1 ' tvvvY 'V

A... .. A

PLOT NO, 3 - BLUE SKY

/IA%

Aio w W I'll!,~' 1 !1`400 1

A03374P LOT, N.3 I -BLUE SKY

8-al4

1 ULTRAVIOLET BACKGROUND SITE NO. 12

DIFFERENCE PLOTS

j PLOT NO.1 -PLOTNO. 2 PLOTNO. 1-PLOT NO. 3

$1 0000 06

0.0 V I)

; .0-00 A0.002

a 000300 320 340 360 380 400 420 300 320 340 380 380 400 4. 0

3 4RVELLN0IH (tMILLIMICNONS) WAVELLNOTH IMILLIMICRO2N33 G


J00 J00 14 400 41!0300 P0 340 H 30 Jlll 400 4.0~

A63675

.,PFigwe 5-12 (Continued).

* .1

I,, 5-1X5

ULTRAVIOLET BACKGROUND SITE NO. 13LOCATION: BLUE RIDGE, CALIF PLOT NO, 1 - CLOUD NEXT TO MOUNTAIN

DATE: MARCH 31, 1970TIME: 13:02 PST EL ANGLE: 00 AZ ANGLE: 195' MA",ELEVATION: 7386 FEETTEMPERATIVE: 38OF PLOT NO, 2 - MOUNTAINR.LATIVE HUMIDITY: 30%SUN ANGLE: 55.80 EL 1940 AZ MAG EL ANGLE: 0° AZ ANGLE: 196' MAG

PLOT NO, I '

PLOT NO. 2


PLOT NO. I - CLOUD NEXT TO MOUNTAIN PLOT NO, 2 - MOUNTAIN

*0.oC- /0

0 70 0,000 ..

L300 320 340 40 3fl 40 300 , 340 3"0 3001 400 420W O WN•L~NiD H I l LLIMICRONBI WAICLEON" (ILLIICRONSI


PLOT NO. 1 - PLUT NO. 2

o .,I.15

0 , o , I\o 4

i -vl .

4CCCC I NE[I - NM, - ' 14 iNj

A63444-1

F'igulre 5-13.

ULTRAVIOLET BACKGROUND SITE NO. 14LOCATION: SAN ONOFRE, CALIFORNIA PLOT NO. 1 - CLOUDDATE: APRIL 28, 1970TIME: 12:50PST ELANGLE: 90 AZANGLE: 2 0 0MAGELEVATION: 110FEETTEMPERATURE: 59 0 F PLOT NO.2- HILL HORIZONRELATIVE HUMIDITY: 420SUN ANGLE: 640 EL 1980 AZ MAC ELANGLE: 80 AZANGLE: 2 0 0MAG

PLOT NOT I

SPLOT NO. 2.


PLOT NO. 1 -- CLOUD PLOT NO, 2 - HILL HORIZON

ti- r

"300 320 340 ,'cl 11 400 ,120 AW~t 320 340 '360 .300l( 400 ,= WO= ~~kAVELkNOTH 'HL IM[UI!MVFI•NUTN 141Lt Itl[,RONS•)

.. ULTRAVIOLET BACKGROIJND SITE NO. 39DIFFERENCE PLOT

" IPLOT NO, 1 - PLOT NO. 2

a-,~.. ..........SO, VPA

4flf .... ....

0 00i4- Q INW.- I' ll l

A L 'Kgure 5-14. E N


LOCATION: SAN MARCOS PASS PLOT NO. 1 - LIGHT HAZA CLOUD PLOT NO, 3 - CLOSE HILLDATE: MAY 18, 1970TIME: 14:09 PST EL ANGLE: 6,70 AZ ANGLE: 3020 MAG EL ANGLE: 60 AZ ANGLE: 3000 MAGELEVATION: 1850 FEETTEMPERATURE: 760F PLOT NO. 2 - DISTANT HILL PLOT NO. 4- BLUE SKYRELATIVE HUMIDITY: 43%SUN ANGLE: 51,50 EL 2300 AZ MAG EL ANGLE: 6,20 AZ ANGLE: 3010 MAG EL ANGLE: 70 AZ ANGLE: 3020 MAG

- - PLOT NO. 4

PLOY NO. 1

PLOT NO. 3 .,•


PLOT NO, 1 - LIGHT HAZY CLOUD PLOT NO. 3 - CLOSE HILL

;U1012

Z=O,0i8• 1"N"0.0010" '"

0006- ,0 000

30 a.. 20 340 360 3arc 400 420 300 320 340 360 340 4010 4 2OkRVELENOTH (MILLIM ROW= kRV[L(NOfH IMILLIMIlCHONS)IcIi PLOT NO, 2 -DISTANT HILL 4LOT NO, 43-0BLUESK

06 400042

320 30420 3oOW•IVILENOTH I MILL INICXONS) I k iELENO111 1 1 ILL I-1lCRONI

M63946..'

F-iguru 5-1G.

ULTRAVIOLET BACKGROUND SITE NO. 15DIFFERENCE PLOTS 4

PLOT NO.1- PLOT NO.2 PLOT NO. 4 - PLOT NO. 1

S•o.ooos

V7 V'E 0.0006

o ý004 v

S.0.0002

z z

0.00u~~~. 0.00001.. . ...2 002 3 360000 421.

300o320 30 0 40 3080 4003420 0,

I~RvL~NwaM II (MLLLflICRONSI

1WRVELENOI•M IMILL IMl(ICKN31 i i

PLOT NO. 1 - PLOT NO, 3 PLOT NO. 4 - PLOT NO. 2

u~ 50.006

0r 0 .0

o 00004

|. V.

.004 002u

oot .. .. ±,.0 4.....f 00.... J6 ........ 36j ........ 0• 4 ', 0" .J a 2.. . . '0•. . . • O (

300 320 340 360 380 400 420 300 320 340 36O 300 400 420WRVA LENOTH (MIIL IIICRON51 U0V1.LENOM 7I M ILLIMICRONN)

PLOT NO. 2 - PLOT NO. 3 PLOT NO.4-PLOT NO. 3

0.0 .~o . - I I - -I. r ..1 1~~~00 003 iNNA

0.001

wo( 10001300 320 340 380 380 400 420 300 320 340 300 310 400 420L A63947 AVELLNOtH IMILLIMICROM51 WAVLILNU'TH IMIL JIIMCNGN31I

F1lgure 5-15 (Continued).5-1'.


LOCATION: BLUE RIDGE, CALIF PLOT NO. 1 - SKY ABOVE MOUNTAIN

DATE: MARC'H 31, 1970 EL ANGLE: -2O AZ ANGLE: 1750 MAGTIME 12A.46 PST PLOT NO. 2 - DISTANT MOUNTAINELEVATION: 7386 FEET EL ANGLE: -3°0 AZ ANGLE: 175'°MAGPLOT NO. 3 - MIDDLE MOUNTAIN

TEMPERATURE: 370F EL ANGLE: -40 AZ ANGLE: 1750 MAGRELATIVE HUMIDITY: 34% PLOT NO. 4 - NEAR MOUNTAINSUN ANGLE: 570 EL, 1860 AZ MAG EL ANGLE: -50 AZ ANGLE: 1750 MAG

PLOT NO. 1

PLOT NO. 2

~~.PLOT NO.4


PLOT NO, 1 - SKY ABOVE MOUNTAIN PLOT NO, 3 - MIDDLE MOUNTAIN

~0.004I

~0 .004

32 -J40000juc )20 34U 3030 J0O 40LI 420 3uu 320 J40 360 300 400 4;0IWdVE ILN~fl, I tiler IMICRONS I WAY t i N1 Ir T H!, I I M 1, ON' 5

PLOT NO. 2 - DISTANT MOUNTAIN PLOT NO. 4- NEAR MOUNTAIN

0 ,01-!r,. ........ .. . . . -, , 1. . 1. 1,, 1** . 1. •,+ - I• -. . .I . .. . . • . ... ., , ,... .1- 1. ...... .. . - , •

4.

t

S• • o.,- ; L

.1,4

•} )U I •i i i i i * i i i e I i i I, ]]ll• i k•.•Ou ( ; 4 ..... i ii i&......... ........ ,,i . . .I *i.. .i *, * , ,*

"*ii~¢ ' 444*) ' H 44jl t ')O! ,• N41N', .44 N4144 "i; 4"1N l''

AFi3 442- 1

4 5-20-1•

-- -

ULTRAVIOLET BACKGROUND SITE NO. 16, DIFFERENCE PLOTS

PLOT NO, 1 - PLOT NO. 2 PLOT NO. 2 - PLOT NO, 3

II

1 0,00k.

0 3 C 40 0 340 360 3, 0 400 I2040n flO 340 360 380 400 420

WAV LENUT 4 0 3LI IMCHNS iiAVLLENOTH m'IN MICRONS)

SPLOT NO. 1- PLOT NO. 3 PLOT NO. 2 - PLOT NO, 4

j~~ %oL 0 .004

~'.O.,.,. /~~~~~~-jj i °,= . . .. .. ............. ''I wo.o0 ,... . ....0,,, 0. . . . ".. . . . . . .a " ol ooA

*200 400360lOG 20 340 30 400 23

rr•O' 0

0380 40

t A VELEN0 I I CRONSI WAVUIINOtH IMILLIMICRON31

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i•~~~~~ loop PLTN.--PO O

I I 0,002•,

U0. 04

- o ,• o o u t .. . .. ...1110 340 360 l 0 4o0 420 J00 30 4 300 0 40 4A0

Figure 5-16 (Continiued).

'-1

:IIULTRAVIOLET BACKGROUND SITE NO. 17

LOCATION: BLUE RIDGE, CALIF PLOT NO. 1 - BLUE SKYDATE: MARCH 31, 1970 70TIME: 12:10 PST EL ANGLE: 7 AZ ANGLE: 230 MAGELEVATION: 7386 FEET

TEMPEATIVE: 30°F PLOT NO. 2 - PINE TREESRELATIVE HUMIDITY: 37%SUN ANGLE: 59.70 EL 1700AZ MAG EL ANGLE: 70 AZ ANGLE: 2290 MAG

PL


PLOT NO. 1 - BLUE SKY -PLOT NO. 2 - PINE TREES

•0.00•.0.006

S0.015, v

o0 .004

SI.00 -ou 1

300 3Uo 340 36(0 300 400 420 300 3120 340 360 380 400 4?,0oRV'ELENOTH ItMILL ICRONS' WR'ELENON H IMILLIMICRONS)

ULTRAVIOLET BACKGROUND SITE NO. 42DIFFERENCE PLOTPLOT NO. 1 - PLOT NO. 2

C0.00 .

A63455-1 WAVELENGTH IMILLIMICRONS1

5-22 Figure 5-17.

ULTRAVIOLET BACKGROUND SITE NO. 18ILOCATION: SAN MARCOS PASS PLOT NO. 1 - BLUE SKY

DATE: MAY 18, 1970TIME: 13:47 PST EL ANGLE: 3.60 AZ ANGLE: 1E50 MAGI

TEMPERATURE: 750 F PLOT NO. 2 - COAST LINERELATIVE HUMIDITY: 43%SUN ANGLE: 570 EL 2270 AZ MAG EL AxGE 4.50 AZ ANGLE: 1550 MAG

I *.. .. ~ .. PLOT NO. 1

IR PHOTOGRAPH .7 -. 9 MICRONS UV PHOTOGRAPH .35 -. 40 MICRONS

PLOT NO. 1- BLUE SKY PLOT NO. 2-COAST LINE

U 0-004.11

300 320 340 380 3a 4 00 420 a00 320 340 3g80' ... 80N 400 420WAVELENGTH II4ILLlflICRONSl I.QVELEN0TH IIIILLIIIICRONS)

- ULTRAVIOLET BACKGROUND SITE NO. 43DIFFERENCE PLOTPLOT NO. I PLOT NO. 2

U000 -

0.004 ~

301 320 34,0 380 380.. 41180 . 4'20WAVELENGTH (lIILLIMICRONS)

A63979-2

Figure 5-18.* 5-23

ULTRAVIOLET BACKGROUND S!TE NO, 19LOCATION: DESERT HOT SPRINGS, CALIF. PLOT NO. 1 - BLUE SKYDATE: APRIL 23, 1970 EL ANGLE: 40 AZ ANGLE: 1500 MAGTIME: 13:35 PST PLOT NO, 2 - DISTANT MOUNTAINELEVATION: 1087 FEET EL ANGLE: 30 AZ ANGLE: 1500 MAGPLOT NO, 3 - NEAR MOUNTAINTEMPERATURE: 780 F EL ANGLE: 10 AZ ANGLE: 1500 MAGRELATIVE HUMIDITY: 9% PLOT NO, 4 - NEAR DESERT FLOORSUN ANGLE: 57,50 EL 2140 AZ MAG EL ANGLE: 00 AZ ANGLE: 1500 MAG j

7 P.~LOT NO.

• .•.... . -•" ... . -• " n I"••L,,• PLOT NO. 2 .0- , , ' . , .f,

PLOT NO, 3

OT NO 4.

S.. .. . . • N , . ,., "-d =.


PLOT NO. 1 - BLUE SKY PLOT NO. 2 - DISTANT MOUNTAIN

"-, i'i--S0 - 02 t

to N"

0 G A .3•0 4LI 42.006 30 4

*o o•/

9 0.130

" 1(10 31) (4(1 300 ( ' " 10 420 300 320 34 0 8(O 300 400 420WP4 r'.41". 0rH Ilt(l '''lCRIN',l 44vl tf(Lf tH lrN( t I I

A63671-1 Figure 5-19.

5-24

< |ULTRAVIOLET BACKGROUND SITE NO. 19

DIFFERENCE PLOTSPLOT NO.1 - PLOT NO. 2 PLOT NO. 2 - PLOT NO. 3

j .'0.003

a 0.002

,, 0 1(10,01101

J '0300 •030 3 80 4'8 43 6 30 • 300 380 400 40 36

~~~~2 300 300 320 WRVL00T 40I0LIICOO * 30 0VL0WAVELENGTH! (M'il.iMl CRON4i1 WAVE;LENGT'H (MlILI, MICRONS)

PLOT NO. 1 - PLOT NO. 3 PLOT NO. 2 - PLOT NO. 4"18

C" (3,(3(4 (M. 0.000 -WO

aa

030.010 0

0,004

,oo oo ,

u' 00.002

,O 002,

L U

.0-000 0.000 .3" 0 320 340 3 0 380 400 42•( 300 320 340 36l 3e0 400 420

WJAVEL3ENGTH (IMILLIMIC RON.SI WAVELENGTH IMILLIMICRON(341

PLOT NO.1- PLOT NO. 4 PLOT NO. 3- PLOT NO. 4

S' '

0.004

30oo 32 340a 360 320 34' 36'L~ 0T( 3010 400 I4.2'WAlVELENGTH (MIL~LIMICRON3I AEENT MLLMCO3

A63672

Z'igure 5-19 (Continued).

5-25

ULTRAVIOLET BACKGROUND SITE NO. 20LOCATION: BLUE RIDGE, CALIF. PLOT NO. 1 - SNOW ON MOUNTAINDATE: MARCH 31, 1970TIME: 13:14 PST EL ANGLE: 20 AZ ANGLE: 2250 MAGELEVATION: 7386 FEETTEMPERATIVE: 39°F PLOT NO, 2 - PINE COVERED MOUNTAINRELATIVE HUMIDITY: 28% 0SUN ANGLE: 54.5' EL 1980 AZ MAG EL ANGLE: 1 AZ ANGLE: 226' MAG

PLOT NO, 1-


PLOT NO, 1 - SNOW ON MOUNTAIN PLOT NO, 2 - PINE COVERED MOUNTAIN

m *o*oL oA

o..00-

.0,004 3,0 0,001

300 320 340 380 380 400 420 300 320 340 360 380 400 420

WRVELEN0TH (MILL ItICRONS) W4VELE(N40? III IIN(ICON3I


PLOT NO, 1 - PLOT NO. 2

NAI .NA0c5

.4ou 320 340 3f00 30t0 400) 420A63460-1 "MOV OT. H r 1(1,"1P I mizc•0ou.5

6-26 igue 5-20.5-26

S... •: ':" -. ' , - " •• .P .,••.•Z ••: : -• :..-,'.,,..., ;'.,,:.':,:i,, , .,.!.:,. :,. _2;


LOCATION: LAKE CASITAS PLOT NO. 1 - BRIGHT HAZY SKY PLOT NO. 4- LAND POINTDATE: MAY 19, 1970 EL ANGLE: +10 AZ ANGLE: 750 MAG EL ANGLE: -2° AZ ANGLE: 750 MAGTIME: 11:19 PST PLOT NO. 2- LAND STRIP PLOT NO. 5 - WATER BELOW POINT IELEVATION: 700 FEET EL ANGLE: 00 AZ ANGLE: 750 MAG EL ANGLE: -2.50 AZ ANGLE: 750 MAGTEMPERATURE: 71°F PLOT NO. 3- FAR WATERRELATIVE HUMIDITY: 49% EL ANGLE: -10 AZ ANGLE 750 MAGSUN ANGLE: 72.5 0 EL 1370 AZ MAG

PLOT NO.1I

PLOT NO. 2

IiimIR PHOTOGRAPH .7 - .9 MICRONS UV PHOTOGRAPH .35 - .40 MICRONS

PLOT NO. 1 - BRIGHT HAZY SKY PLOT NO. 3 - FAR WATER

... .. . .. .. .. ..,. ... ..0 . .. . .

0 S44L W•"MC ILTN.2-LN TI LTN.4-LN ON

"0-0.006

uu

' 0

I;~ 2 300 320 340 380 360 400 420 300 320 340 380 300 400 420I•RVELEN0TH ( IIILLIM11CRONl-, H NRELFN0TH (rIIlLL IMICRONH )

awascc ,00

-5-2

0 4t

0 . 0 0 0. ... ... .....' 8 6 ....

2 000 0 . 0.8002W . 38 00

~0.004

300 320 340 3810 380 400 420 300 320 340 360 300 400 42UI4RVELENOTI (KILLIMICRONdO) WffVCLENOTH (MILLIMICRONO)

A63948-1

Figure 5-21.

5-27

.41 ý--;IA6______________

ULTRAVIOLET BACKGROUND SITE NO. 21DIFFERENCE PLOTS

PLOT NO. 5 -WATER BELOW POINT PLOT NO. 1- PLOT NO. 4

* ao 000

o o

%0.0°

u

"'V i "1 . . . . ........ tS..........N........ 3' -81 . ..... 44 0 .......... ....... 30, 00 32 4 3G 8 4 0 4 C'".1 am 34 360 360 400 420 30*00 32 .40 3.0 38 0

MjLUOThN fl(MILLIMICRONS) WAVELENI TH (M ILLIMIICRONS)


3c0.006

€I ,

0,0041

300 340 341' 380 360 400 420 300 320 3'0 3C0 36(0 4dC 420W•VLL/,NO'II UI ILL IMICRON,5 I 4 v W 4rV . 1 NT IIIill, ,IIICRONOI j

PLOT NO. 1- PLOT NO, 3 PLOT NO, 2 -PLOT NO. 4

u u

-Iz 7 .

30 20 340 36 3oa 400 420 300 320 340 330 380 4 cc 420

W8vFL•I0"1

1 IMILLIIcjON$I 4O/N.I WVE4Ir0T IILL II0CROt 1IA63949

5-28 Figure 5-21 (Continued). .

L ::::.z .. . ., ,.- .. . - . ,, . . ,, ,

IVII ULTRAVIOLET BACKGROUND SITE NO. 21

DIFFERENCE PLOTS


•0,0001

-0'-4-0i"

:0 .033

A0.0002rIiiooo I . I .

N . A = i'

0 .003 -C4

0.00 ý0o0az lc

38C 320 340 36 3d( 400 420 300 320 3;0Q CO dlIC 00 420

6RVtNO'lt Ir I•LIMICR3JNFI WqJLL I I fm ICRONS

j

PLOT NO' 3 -PLOT NO. 4 PLOT NO. 3 -PLOT NO. 5

I a0,003,o ,,0 .0040

~0 .102-

00.00 01 0 i330m o,•o 0 otoi 3 4 420 3GO U3 to0 3 150 4- ' 420

S~PLOT NO. 5 -PLOT No. 4

"• • .1 E- vk i '

4- ;- -lNIV,

z V U~"- t I

310 le 0 3.0 3 61 38C 420

A63950 F

Figure 5-21 (Continued).S~5-29


LOCATION: SAN ONOFRE PLOT NO. 1 -WATER

DATE: MAY 14, 1970TIME: 14:27 PST EL ANGLE: -30 AZ ANGLE: 1930 MAG

ELEVATION: 110 FEETTEMPERATURE: 72

0F PLOT NO. 2 - HILLSIDE

RELATIVE HUMIDITY: 60%SUN ANGLE: 450 EL 2350 AZ MAG EL ANGLE: -30 AZ ANGLE: 192 MAG

PLOT NO.,

PLONO1

IR PHOTOGRAPH .7 - .9 MICRONS UV PHOTOGRAPH .35 - 40 MICRONS

PLOT NO, 1 - WATER PLOT NO. 2 - HILLSIDE

0OUNRAL "v"""IC - M RAL oVAsO

V)0 .001

0. . . . . .......... ...... . ........ 00. . 0 . . . .. 0 . ,300 320 340 360 380 400 420 300 320 340 300 380 400 420

aRVELE.NOTH (iILLIMICROI WAVELENGTH (MILLIMICR0NSI

ULTRAVIOLET BACKGROUND SITE NO. 47DIFFERENCE PLOTPLOT NO. 1 - PLOT NO. 2

;o .o, - U,-4--••r•,M.ALV_,,.M "W-

.0,002,

o0.002'

• o.oaoo, .. . . . . . . . . . . . . . . . . . ........ ........o d6 * • =300 320 340 360 360 o 420

WAVELENGTH IMILLLIMICRONSIA63779-1

Figure 5-22.5-30

Aa 2S... ... : • . .. .. . ..__ _ _ _ .. . .. : . . ... .. . _ _-__ _ , .. . . , _ ._ = - .. .-I


LOCATION: SAN ONOFRE PLOT NO. 1 - BLUE SKYDATE: MAY 14,1970 0TIME: 1417PST EL ANGLE: +,2 AZANGLE: 195 MAGELEVATION: 110 FEET

TEMPERATURE: 720F FLOT NO. 2 - WATER HORIZONRELATIVE HUMIDITY: 60%SUN ANGLE: 510 EL 2300 AZ MAG EL ANGLE: -. 2' AZ ANGLE: 1950 MAG

1PLOT NO. 1

PLOT NO. 2

I

SIR PHOTOGRAPH .7 - .9 MICRONS UV PHOTOGRAPH .35 - .40 MICRONS

PLOT NO, 1 - BLUE SKY PLOT NO. 2 - WATER HORIZON0.016 **~.D'A~wm .5 N j

=0,0000

- 004

01000 .... .. . .... .. .. ... ....0...300 320 340 360 380 400 420 300 320 340 360 380 400 420

VFLENOTH IILLIICRONS) WPVELENOTH (t¶ILLIMII CRONSI


PLOT NO. I - PLOT NO, 2

0U ,002

, 0.003 . .. ...... ..

UI

0 t.000

300 320 340 360 380 400 420ARVELENOTH IIILLI4ICRONS)

•",63778.1

Figure 5-23.

5-31.

II..' "• "• .;,:• '

ULTRAVIOLET BACKGROUND SITE NO. 24LOCATION: SAN ONOFRE, CALIF PLOT NO, 1 - DISTANT CLOUD OVER OCEANDATE: APRIL 28, 1970 EL ANGLE: 2° AZ ANGLE: 1950 MAG

'•TIME: 13:05 PST PLOT NO. 2 - SKY NEAR HORIZONELEVATION: EL ANGLE: 20 AZ ANGLE: 1950 MAGTEMPERATIVE; 59° PLOT NO. 3 - OCEAN HORIZONRELATIVE HUMIDITY: 40% :0SUN ANGLE: 62.50.5 AZ ANGLE: 195 MA

SPLOT NO. Ji I •• ,

PLOT NO. 3


PLOT NO. 1 - DISTANT CLOUD OVER OCEAN PLOT NO. 2 - SKY NEAR HORIZON

1 .0

ccc

300 3210 340 380 380 400 420 300 320O 343 380 380 4,00 420 -4~qV8LEN0?H (IILLI,"ICHONOI| PVe.LO.NOTII (IIILLIS!tCRONO)

PLOT NO. 3 - OCEAN HORIZON ,

3•0,000 32•0 3410 380 380 4003 42'0

, 44-1Figure 5-24.

5-32 -,

. .:. -

IL . ....

i ULTRAVIOLET BACKGROUND SITE NO. 24

DIFFERENCE PLOTSIPLOT NO. I PLOT NO. 2 PLOT NO. I PLOT NO. 3

0-0.00

'0-oo - 4U A N AI Y A

W O-000.00 • .. .. .. .. .. .. .. -•.0-,_.,,. .

JOG 320 340 360 3 40 2 0 3 o0 32003 4 '03,0 80 00 42'

WAVELENGTH (M|ILLIMIMNS) WAEEGTML•MCUS

"" aL Li

5-33 [N1 I•.

0..004

1300 320 340 36 34 a0 42M 0 2 4 0 8 400 4204AV~~~~~LEN~AVLEGT (MLLIICRNS WVEENTHIMLLI1CRNS

[ a

A63447a000 32


5-33/5-34

Ji

•. . ., •. • , ' ', ,, . -,..:k'"

, Iz

i~i: JSECTION 6

:,i. • PHASE-Ill IR MEASUREMENT DATA

' -

,i IS!*

1 ,

Ul I

11

*i.__ __ __,_ __ __ __ __ .. ..... • .

"~ 1

Section 6I PHASE Ill IR MEASUREMENT DATA (2 -1 2 . 8 1A)

This section presents the spectral radiance data from 8 natural background sitesI obtained during late 1974, These data were taken at San Clemente, California and repre-

sent the first spectral data taken using a new 2-14p interferometer. The San Clementemeasurements were performed to obtain data for typical ocean/terrain background sites.

Background spectral radiance data from each of 8 different sites are presented in", I Figures 6-1 through 6-8. Each figure contains the absolute spectral radiance (in micro-

watts per square centimeter par steradian per micron) of two portions of the backgroundfor the spectral region from 2 to 12.8 ;. These absolute radiance spectra were obtainedby referencing the measured interferometric data to a source maintained at liquid nitrogentemperature (77 0K) thereby removing instrument radiation components from the data.The data typically represent the coherent average of interferograms recorded over a 10second time period. In addition to the absolute radiance spectra, a radiance differencespectrum is presented in each figure. This spectrum was derived by taking the differenceof the two absolute spectra in the wavelength domain. To complement the spectral data,infrared photographs are provided which illustrate the relative radiation of the measure-

ment site in three spectral bands. For the near-IR band (. 75 - 90p) an infrared photo-* 1:• graph is given. Thermal images are provided to describe the spacial radiation geometryin the mid-IR (3.6 - 5 . 4 1) and in the long wavelength-IR (7.5 - 13 1) spectral regions.Additional information given includes temperature, relative humidity, line-of-sight angles,and sun angles,

The radiance spectra presented in Figures 6-1 through 6-8 display graybody con-tinuum radiation and molecular emission/absorption structure. The graybody radiationcomponents evolve from two different sources and appear in two distinct spectral regions.In the 2 to 3pspectral region the radiance spectra of certain backgrounds display a hightemperature graybody characteristic. This is due to diffuse reflection and scattering ofsunlight. In the 3 to 13 1 spectral region a definite low temperature graybody continuumcan be observed in all the absolute radiance spectra. This component provides the pro-

dominant spectral shape in this region and is due to the ambient tempcrature emission ofthe constituents of the scene,

The radiance difference spectra shown in the C portion of Figures 6-1 through 6-8Sall show a significantly larger contrast in the 8 - 13A spectral region than in the 2 - 81

band. The molecular line structure inherent in the absolute radiance spectra become muchmore pronounced in the contrast spectra. This is because the graybody continuum portionof the absolute spectra are generally quite similar both in amplitude and in spectral shape.Consequently, the major difference between the two absolute spectra is in the molecularlire structure.

I1,6-1

.•i

"77

THEMU1L IMAGE(2-5 5,#) NEAR-ZR P'HOTO(.75-.9O,&) THEW~AL IMAGE 7.5 -13 P

* A ~Udiance Spectrum of Terrain B. Radiance Spectrum of Water

.

C.- Terrain/Water Difference Spectrum

Location: San Clemente, CA* Date: October 16, 1974

Time: 11:21 P.D.T.IOU Temperature: 78OF

Relative Humidity: 27%

I Azimuth: 165' Mag.'1Elevation: .. 50

Sun Azimuth: 1540

Sun Elevation: 440IWAVIIN01 01CONIFigure 6-1. Spectral Radiance Data From Background Site No, 2 Terrain/Water

6-2 5

"NI

ITHEW'14 IMAGE(2-5.5ýt) NEAR-IR PHOTO(. 75-.90,") THET4AL IMAGE (7. 5 -13 A

IA. Radiance Spectrum of Cloud B. Radiance Spectrum of Sky

2~0 4 ItO1 WA£EN1 "1MNI C. Cloud/Sky Difference SpectrumI ! Location: San Clemente, CA

Date: October 1.6, 1974Time: 11:35 P.D.T.Temperature: 780F

if'Relative Humidity: 27%Azimuth: 1900 Mag.Elevation: +40

Sun Azimuth: 1580Sun Elevation: 450

I ~Figur'e 6-2. SPectral Radiance Data From Background Site No. 3 Cloud/Sky

6-3

I ___IN

k G eIVS?ý1ý

.~;' -4

THERMAL IMAGE(2-5.5,K) NEAR-IR PHOTO(. 75-.9OýL) THEBML &*NMD*GE0. 13P)Jf

A. Radiance Spectrum of Sand B. Radiance Spectrum of Surf

'to mo2

C. Sand/Surf Difference Spectrum -

Location: San Clemente, CA

Date: October 16, 1974Time: 11:41. P.D.T.Temperature: 78OFRelative Humidity: 27%

I Azimuth: 1700 Mag.Elevation: - 7,50Jun Azimuth: 1610Sun Elevation: 460

Figure 6-3. Spectral Radiance Data From Background Site No. 4 Sand/Surf

6-4

THEmRt&L IMAGE(Z- 5.5,.) NEAR-IR PIIOTO(.75-,90)A) TIIEF44L IMAGE(7.5 -13A4)

A- ARadiance Spectrum of Rock B. Radiance Spect rum of Water

C. Rock/Water Difforence Spectrum

Loo~ation: Sani Cluemente, CA11 Date: October 16, 1974Time: 11:4E P.D.T.Temperature: 78OFIRelat'Ave Humidity: 27%I ~Azimnuth; IM' Hag.

Suai Elevation: 46.50

Figure 6-4. Spectral Radianc~e Data Fromn Background Site No. 5 Rock/Water

6-5

A,,A 11:!

THERMIL IMAGE(2-5.5ý) NEA6R-ta PHOTO(.75-.90,u) THEMIAL IMAGE(7.5 13MS)

A. Radiance Spectrum of Ocean B. Radiance Spectrum of Cloud

"• ............ .......

C. Ocean/Cloud Difference SpectrumIILocation: San Clemente, CA

Date: October 16, 1974Time: 11:54 P.D.T.Temperature: 78OFRelative Humidit: 27%.Azim"uth: 2200 Ma.Elevation: + 10Sun Azimuth: 1660

Sun Elevation: 46./0

Figure 6-5. Spectral Radiance Data From Backgruund Site No. 6 Ocean/Cloud K6-6

A[RdineSpcrm fOea .Raine pcru fClu

* n

IIT,

A161ATIHEmRKA. IM&GE(2-5.5/.) NEAR-IR PHOTO(.75-.9Oý&) THERMAL WAGE (7. 5 -13 P

I

A.Radian~e Spectrum of Mountain B. Radiance Spectrum of Sky

II O

1C. Mountain/Sk; Difference Spectrum

V Location: San Clemente, CADate: October 16, 1974Time: 12:15 P.D.T.Temperature: 78OF

too Relative Humidity: 277.

Azimuth: 1050 Mag.Elevation: +2

~~ Sun Elevation: 47.3O

1 ~Figure 6-6. Spectral Radiance Data From Background Site No. 7 Mount~ain/Sky

6-7

NOT AVAIIABLE 9

THERMAL IMAGE(2-5.5pt) NEAR-IR PHOTO(.75-.9Op) THELMAL IMAGE(7.5 -13 A

A. Radiance Spectrum of Trees B. Radiance Spectrum of Sky

to It

C Tres/Sk Diferene Spctr[

Loain San. ClmntC

Da6 Ocoe 1,17

IElovation: Sa Cl80 tC

I unAximuth: 2150ag

V~, Sun Elevation, 41.50

Figure 6-7, Spectral Radiance Data From Background Site No. 8 Trees/Sky -

6-8 -

I NOT AVAILABLE

ITILEMAL IMkGE(2-5.54.) NEAR-IR PHOTO(.75-.90ji) THELKILL IM4GE(7.5 -13/4)

A.Radiance Spectrum of Sky at Bo Radiance Spectrum of Sky at100 Elevation 200 Elevation

C. 100 Sky/2O00Sky Difference Spectrum

.......... Location: San Clemente, CADate: October J6x, 1974Time: 14:42 P.D.T.

~IOQTemperature: 80OFRelative Humidity: 35%Azimuth; 1150 Mag.

1 Elevation: 200/1004 _ _ Sun Asimiuth: 2210

-A Sun Elevation: 38.90

Figure 6-8. Spectral Radiance Data From BackgrTound Site No. 9 Sky at 200 and 100E levation

6 9 6 1

777777776779/6-10777 17771

Documents

r'BACKGROUND SPECTRAL 8ADIANCE / AND CONTRAST IN … · r'background spectral 8adiance / and contrast in the i nearu, m-ir, and lwir regions / ... g. c. halterman sf. a. jepson r