ri or of the 
the field 
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the incoming 
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er compensa- 
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’ covered sky. 
covered sky, 
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the angular 
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■ SA 100/300 
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tes for one 
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ant targets, 
herry picker 
is reproduci- 
sured targets 
us structure 
ngle measure- 
ments, spectral reflection data to photogrammetric 
pictures and video signals. That requires great care 
in the organization and recording to guarantee for 
later examinations to have the data in acceptable 
form available and to assure an easy access to compa 
rable informations for the analysis steps. Conside 
ring the number of plant species, independant culti 
vations and cycles, there are about 150 or 200 data 
sets to expect within one year. 
Data collection and analysis only will be practicable 
if the computer technique is already used in the 
field campaigns. According to that necessity, two 
personal computers will accomplish data storage in 
the field. One PC acts in the laboratory for direct 
collection of spectroscopic data from the pigment 
analysis and for recording of all other immediately 
gathered agronomic parameters. The second PC controls 
the SA 100/300 spectro-reflectometer via communica 
tion line and serves as recording device too. Addi 
tionally all météorologie data will be put into that 
computer. 
The use of direct digital data recording allows to 
meet the requirements of a strong organizational 
concept with adequate labeling of corresponding mea 
surements and sophisticated storage techniques to 
keep a clear structure in the heterogenous data. 
4.2 Pre-processing and examination 
The effort for pre-processing varies with the type of 
data. Most of the agronomic and météorologie data is 
available in the form which is required for further 
examinations and they will be fed directly into later 
procedures. 4ntp* 
Some more work has to be investeduie pictoral stored 
information. The photogrammetric stereo pictures have 
to be measured stereoscopically to provide informa 
tion for the determination of plant geometry. The 
video signals first need to be digitized, then cali 
brated radiometrically and geometrically and after 
that some image processing steps have to be applied. 
After correction and enhancement the derived angular 
densities feed into atmosperic simulation models in 
order to have information about the intensity distri 
bution of the incoming radiation. 
During the examination procedure there are a lot of 
different stages to consider. First of all, the 
computer technique provides some very helpful tools 
like graphical presentation or plotting of data. This 
allows visual interpretation of long data columns and 
simplifies the detection of common features or corre 
lations. 
In a next step methods of statistical analysis have 
to be used. This is important to detect variations in 
the data which have to opposed to possible origins 
like exterior influences, the measuring technique 
itself or unknown factors. 
In a further step corresponding data has to be com 
pared. This might be done using data of different 
type but from the same sampling date, or using data 
of one type and comparing results form different 
dates in the growing period. 
Besides these more or less statistical procedures it 
is necessary to find a powerful way to correct the 
radiometric data for exterior influences. One set up 
could exist in a simulation model which takes the 
atmospheric situation and the geometrical structure 
of the plant targets into account, whereby the plant 
geometry could be described parametrically or sta 
tistically too. 
But the practicability of these thoughts has to be 
proved during the first measuring campaigns. Already 
the first analysis of all informations will indicate 
which way to go and where further improvements in 
functional set ups or measuring techiques are re 
quired. 
5. CONCLUSION 
The presented project which is now in the stage of 
the first measuring campaigns aims to provide basical 
infomation for a better understanding of the inter 
action of electromagnetic radiation, plant reflection 
and physiologic as morphologic plant parameters. In 
the present case this is done to improve the power of 
remote sensing techniques for yield estimation in 
Europe. 
6. Ackowledgement 
This project is sponsored by the German Ministry for 
Research and Technology under contract № 01 QS 094 7 
and is conducted by Prof. Dr. W. Klihbauch, Institute 
for General Plant Cultivation and Prof. Dr. G. 
Kupfer, Institute for Photogrammetry, both at Univer 
sity of Bonn. 
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