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5,4 How is the completeness and accuracy of the graphical plotting checked 
during or immediately after the work? 
24 answers. 
In 12 cases check of the completeness and accuracy of the map is made 
by the supervisor during and after the plotting work. 
In 12 cases the check is performed after the plotting. 
In 4 cases field-check of the map is accounted, 
In 5 cases check of the completeness of the map is performed by comparing 
the map with contact prints or enlargements of the aerial photographs. 
5,5 Which are the requirements for control points for various plotting 
purposes concerning the number and positions of such points ? 
24 answers, 
In general there is for plotting purposes need for 2-4 control points in 
planimetry and 4-6 points in elevation. The points should preferably be 
located in the corners and in the center of the models. 
For triangulation purposes there is need for complete control of the first 
model and 2 control points after 6 models, or 2 control points in each of 
the first and last models and in the middle of the strip if the number of 
models do not exceed 20, or 1-4 control points/100 um“ and elevation 
control at the edges of the models, 
5,6 For which purposes and to which extent are field checks required 
concerning 
5,61 the completeness of details ? 
5,62 the identification of objects ? 
5.63 the horizontal accuracy ? 
5.64 the vertical accuracy? 
22 answers. 
In general the completeness of the map and the identification of objects is 
checked in connection with the completing work in the field. In some cases 
field inventory before the plotting is used. 
In 11 cases field check of the horizontal accuracy is accounted. Between 
5 per cent and 30 per cent of the map is checked in the field. 
The vertical accuracy is checked in general, usually with terrain measure- 
ments. In several organizations 85-95 per cent of the elevation discrepan- 
cies must be less than half the contour interval.