Dept, of Remote Sensing and Geoinformation, Military University of Technology, Kaliskiego 2, Str. 00-908 Warsaw, 
Poland - (wdebski, pwalczykowski)@wat.edu.pl 
KEY WORDS: Hyper spectral, Acquisition, Camera, CCD, Image, Video 
ABSTRACT: 
Remote sensing uses many different types of imagery for interpretational purposes. Multispectral photography has shown 
to be of especially high interpretational value. During remote sensing studies which are done “in situ”, determining spectral 
reflectance coefficients of any given object is crucial. Spectrometers are usually used in acquiring such data. The authors of such a 
study have used an equipment set consisting of a digital video camera and an electronically tunable filter. The set is designed to work 
in the visible range 400-720nm. The matrix in this camera has a resolution of 1392 x 1040Px. It is capable of binning (the joining of 
pixels) 2x2, 4x4 and 8x8, which allows for the increase in sensitivity at the loss of resolution. Monochrofnatic images acquired by the 
camera have a radiometric resolution of 12bits. The images are saved into the controlling computers memory by means of the IEEE- 
1394 FireWire interface. The camera has a fully automated exposure mechanism together with an ROI function. The electronically 
tunable filter allows for the acquisition of images of a lOnm band, with a O.lnm step, within the given spectral range. Special 
software had been designed to control the set (the camera and filter), which allows for the acquisition of any chosen sequence of 
images within the entire visible range of the electromagnetic spectrum, as well as their primary processing. On the basis of a 
sequence of images, the spectral reflection coefficient can be determined for any objects within the scene. The image sequences can 
be acquired in laboratory conditions, as well as during fieldwork. 
The article describes the methodology in acquiring imagery using the video camera and the electronically tunable filter, as 
well as the determining of the spectral reflection coefficients. Additionally a comparison will be made between the reflection 
coefficients obtained by means of a spectroradiometer and those derived from the registered imagery. 
1. INTRODUCE 
In field measurements of light reflectance play an 
increasingly important role in researching the environment using 
remote sensing techniques. These are essential in both 
determining an appropriate spectral band, which is to be 
registered, as well as in aiding in the correct interpretation of 
acquired multispectral imagery. Obtaining the maximum amount 
of imagery about the value, character and variations of the 
spectral reflection coefficients as well as their dependency on 
lighting conditions guarantees a more complete image 
interpretation. The measurements of the incident light and the 
radiation reflected by the object at the moment of registration are 
key. At the stage of planning a way for the acquisition of images 
for remote sensing purposes, it is essential to know the 
relationship which describes the contrast between the object and 
the background. The registering system should measure its 
maximum value. To ensure full remote detection it is 
recommended that an appropriate channel is found, in which 
there is a considerable difference between the reflection 
characteristics of the object and the background - in other words 
there is a high contrast between and object and the background. 
During “in situ” studies, different types of spectroradiometers 
are used to determine the reflectance characteristics of objects. 
This however requires the use of complicated procedures to 
obtain accurate results. Together with the appearance of 
electronically tunable filters on the market, the authors propose 
the use of a video camera with such a filter to obtain such 
information. 
2. THE SET DESIGN 
The hyperspectral set, designed and created at the 
Military University of Technology in Warsaw, consists of the 
following elements: 
- An electronically tunable narrow banded optical filter 
- A monochromatic digital camera 
- Software used to operate the hyperspectral acquisition of 
images 
Tuneable 
filter and 
control 
module 
lens 
Digital 
camera 
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