%o nm
acts
or
1ctions.
1e
there
m X
it
pet-
, age
Conclusion
The instrument system IRIS makes it possible to analyze multispectral
aerial photographs in a very convenient way. In particular it is possible
to carry through calibration procedures very efficiently. Preliminar
studies comparing spectral signatures determined with multispectral
photographic technique and using a tele-spectro-radiometer show good
agreement in spectral response. The present study also reveals some
discrepancies between the results of the two methods that have been
compared. The causes are expected to be found in the registration
process employed at the calibration. The present scheme of evaluating
multispectral recordings should offer good means to analyze and ultima-
tely remove such discrepancies.
Acknowledgement
We wish to thank Dr Leif Wastenson, Department of Physical Geography,
University of Stockholm, Dr Nils Aslund, Physics IV, Royal Institute
of Technology, Stockholm, Dr Rolf Bergstrom, Boliden AB, Dr Claés Pilo,
Swedish Space Corporation, for their support during this study. Thanks
are extended to the Swedish Space Committee, the Swedish Natural Science
Research Council, who financially have supported the study and the
National Land Survey of Sweden for their photography and laboratory work
and Boliden AB for support in the field work.
References
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