5
Jtogrammetric
purposes led
Geodesy and
; of the natio-
00, 1 : 1,000
er large parts
mmetric me-
on scales of
> large scale
g out a wide
hich resulted
above menti-
ispecially the
the 1st and
nethod.
Cartography
aerial photo-
togrammetric
led out on a
l points. The
the scale of
a mean error
are used for
-armed cross
ography. In-
of applying
•ticularly for
lods used in
cy CSc. The
s computers.
>ased on two
ve the deter-
and the ela-
lined points,
positives are
on the map
scale. The next stage is the classification of the plotted objects and the identification of mar
ked points. According to the enlagerments the project of the supplementary geodetic work is
carried out.
The actual photogrammetrical plotting is effectuated especially during the mapping on
a scale of 1 : 1,000 mostly by the numerical method. The coordinates and other information
are registered on the manuscript as well as on the punched tape in the international teleprin
ting code No. 2. The registered information is used for area calculations and in some other
cases, the planimetry is represented by an automatical coordinatograph. In addition to the
planimetric element the relief is plotted by contour lines with contour intervals of 1 m.
The following spaces which have not been plotted (owing to the fact that some subjects
of measurement are not represented on the photographs or that marks are damaged or lost
etc.) are remeasured immediately after the photogrammetric plotting by geodetic methods. By
the polar method and using Zeiss double-image telemeter BRT-006 we have obtained very
good results. Specialized groups draw up the map sheets and the written surveying docu
ments.
Experiences with the method of photogrammetric survey show that a precondition for
the successful survey are photographs of high quality with contrast control and photographs
with a shrinkage difference of about 0,04% and with a small unregular shrinkage for the
graphical plotting. To ensure results of high accuracy the planimetrical points are marked
and numerical methods are used in orientation processing.
For countryside surveying wide-angle cameras, especially those of 23 x 23 cm type arc
very convenient but for towns the use of normal cameras is recommended. The plotting instru
ments must be continually checked and squared on to achieve guaranteed plotting accuracj'.
The precise plotting of towns represents a technological problem of the photogrammetric
methods. That is why present photogrammetric research aims at solving it.
III. Special photogrammetric works
The method of terrestrial photogrammetry can look back on forty years of tradition in
Czechoslovakia. This method has been applied on a wide scale recently in various technical
branches for special surveying tasks.
Terrestrial photogrammetry is most frequently used for the elaboration of contour line
plans for stone quarries where the output and the projecting of far-reaching coyot-hole blasts
must be followed. It also applied where supplementary measurements of impassable rock for
mations must be taken for surveyings on large scales, for contour plans of spoil banks and
for the surveying of transversal overburden profiles in opencast mines, in raw material or
coal depots of industrial establishments as well as for the planning of road constructions or
reconstructions in mountainous territory.
Terrestrial photogrammetry was also applied in archeology (Slav mortuary at Mikulcice-
South Moravia), geology (the disastrous landslide at Handlova-Slovakia), in architecture
(the vault reconstruction of the baroque temple St. Nicolas and the historic buildings of the
Prague castle), in hydrology (determining the Danube streamline, in measurements of sand
models of river channels) and in railway constructions (measurements of passage profiles of the
overbridges, of tunnel faces and transversal profiles in the driving of underground works).
Short distance photogrammetry was successfully applied in measuring the changes in
models of the overlying layers of deep mines, in plotting the water level contours near piers
and other water constructions and in determining the deflection of reinforced beams.