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comparison between a Photogrammetric 
plotting made with an analytical instrument 
and a plotting performed with techniques of 
digital Photogrammetry, in terms of 
differences of points coordinates. 
2. Objective and execution of the search 
The test has been conducted using a couple of 
frames in white and black of the territory of 
Fasano (BR) during a flight for the realisation 
of the cartography to the scale 1:1000. 
The characteristics of the flight can be so 
reassumed: 
• Metric Camera: RMK Zeiss 
• Focal distance: 153 mm 
• Average of the frame climbs: 1:5000 
• Area covered by every frame: 1 Km 2 
The software used in the Photogrammetric 
Digital process has been Stereo view 300 
developed from Menci-scientific software and 
kindly envoy to disposition from the Nikon 
Ins. S.p.A. 
The fundamental characteristics of this 
Photogrammetric System can be so reassumed: 
• image processing; 
• vector processing; 
• models orientation; 
• 3d digital model representation. 
With reference to the models orientation, the 
software allows the use of different 
algorithms: autocalibration, classic method, 
bundle block adjustment, space resection. 
The Photogrammetric Digital System 
Stereoview allows the stereovision through a 
pair of active polarised glasses. 
The digital photogrammetric system has been 
installed on a PC which characteristic can be 
reassumed: 
• processor Intel Pentium II, 333 Mhz; 
• graphics card Matrox Millennium II, 4 Mb 
VRAM; 
• video Nokia 445X multysinc, vertical 
frequency of refresh of 85 Hz 
• resolution of 1280x1024. 
The images used in the digital plotting have 
been opportunely scannerized. 
The transformation of a metric frame in a 
digital image is today a very easy operation. 
It is well known that the digital sampling can 
happen both with a correct control of the 
induced deformations, from a 
photogrammetric point of view, through 
expensive and sophisticated systems and with 
easy and economic plain scanners destined to 
the market of diffused computer science. 
With both the typologies of instruments of 
acquisition, the resolution can arrive to high 
values (from 1200 to 4000 dpi) but only in the 
first ones we have a checked opt-mechanics 
construction and of extreme quality. 
The answer and the radiometric constancy of 
both the instrumental classes is of high quality 
and it follows a continuous progress caused by 
the increasing question of digital process. 
Vice versa the correct sizing of mechanics, 
dimensional stability and the geometric 
repeatability in the acquisition of the sampling 
are characteristic possessed only by the most 
expensive systems, projected and built 
specifically for a photogrammetric use. 
For this experience we have followed the most 
economic road, based on the use of a scanner 
of good quality but not specifically projected 
for Photogrammetric uses. 
The original frames have been numerized with 
a plain DTP scanner Umax formed A3 of 
average quality. 
To avoid more losses of definition and to not 
introduce ulterior geometric deformations, the 
negative ones has been acquired in original 
B/W directly; subsequently we have effected 
the inversion of grey tones and some 
numerical filtratures to have a control of the 
general contrast and an increase of apparent 
neatness. 
In this way, we have obtained two TIFF files 
raster in gray scale, with a resolution of 1400 
dpi and a dimension of around 170 Mb each. 
The dimensions of the ground pixels, equal to 
around 11 cm have naturally determined, as in 
all the Digital Systems, the resolution in the 
measure of the image coordinates. 
To be able to go up again to the correct image 
of the acquired photo it has necessary become 
the calibration of the scanner before 
proceeding to the acquisition of the images, in 
way to obviate to the drawbacks of inherent