- 585 - 
=d in the 
c) Studies of structural geology on a regional basis 
d) Rice fields behaviour 
e) Rivers, lakes and sea pollution 
f) Fresh water springs along sea shore 
g) Paleoriver beds detailed mapping for civil enaineering 
70 the fol- 
purposes. 
nd Volcano 
EMPLOYED TECHNIQUES OF DATA ENHANCEMENT 
The study of all the collected data may be divided ba 
sed on the employed wavelength (visible, photographic I.R., 
thermal I.R.) and on the way of recording (photoaraphic or 
ino rivers) 
electronic). Hereafter we will describe the employed techni 
ques of data enhancement dividing the argument into the fol 
lowing steps. 
ALUS) 
- Visible and photographic I.R. 
1 - Multispectral photographic techniques 
a) false colour composition 
b) density slicing 
c) masking and masking slicing 
2 - Multispectral electronic techniques 
a) slicing 
b) electronic images chopper 
c) digital approach 
NES ) 
- Thermal I.R. 
1 - Electronic processes 
rent kind. 
a) slicing 
b) sum, subtraction 
., no a) 
c) derivation, integration 
d) ratio, product, square root and power 
iollowing 
2 - Photographic processes 
a) additive synthesis 
b) density slicing of difference and ratio. 
Visible and photographic:multispectral photographic techniques. 
thermal 
The electromagnetic radiation coming from a surface 
( both emitted or reflected) carries information that can be 
;na slo- 
;st to 
>n between 
jreen cover. 
detected either by our eyes, either by instruments, such as ra 
diometers, scanners, photocameras. This information depends 
on the temperature and emissivity of the investigated surfaces 
( opaque surfaces ) following this law : 
n = £ s cA ( m„cvn + (-i-<gNi