Photogrammetria, XIX, No. 6 
and: M x 2 = (F max W max ) 2 P + Ty2 max 12 + L 2 \ 
M 2 2 = (V min Ty max )2 P + W 2 max 12 + L 2 C (6) 
^3 2 = (^ax W m J* * P + W\ iQ l 2 + L 2 ) 
In above relations V max = Z^ x : c mln , V min = Z min : c max and W max , W mia are the 
maximum and minimum transmission ratios from the projection to the tracing style. 
Usually we have W m ,„ = IF" 1 
1 max* 
When solving the systems (5) and (6): 
and: 
R, — Rc, 
t = 
(V V i w 
' max min 7 max 
R x R 3 (R x R 2 ) V v 
w W 
max ,r min 
*3 ^max ^min 
(^max-^min) W 
P = 
M x 2. 
■Mo 2 
(V\ 
V 2 i ) W 2 
r min-' 
M x 2. 
M 3 2 
max 
(MJ — MJ) U2 r 
(7) 
l 2 = 
i.'i/ ¿5 i/i/ /; i i/z »/ w , 
min' " max 
7.2= M2 CV W ■ ) 2 V 2 — W 2 ■ l 2 
irj.^ v v max min' / rr mm 1 
(8) 
(V\ 
V 2 i ) W 2 
r min-' rr ti 
R v R 2 and R s are distortions suffered in the process due to the disturbances of the 
group 2) (r, t, T), while those of M X ,M 2 and AT 3 are caused by random effects (group 1) 
(A, l, L). A separation of both is possible only if specific standard inputs (forcing functions) 
are applied to the dynamic system. 
The geometrical or the static distortions are also contained in the output. They are 
expressed in the slight shifts of the phase if a sine-wave is used as the input. Their ap 
propriate evaluation, however, would be more complicated and less accurate than the 
conventional grid measurements. 
For an efficient separation of disturbances both projectors have to be tested separately. 
A stereoscopic observation and plotting would present less information on the dynamic 
performance. 
III. 3. Input. 
The analysis in the non-dynamic part of the system seems to be rather complicated 
due to the process (information flow) within the human operator. For a dynamic evaluation 
of the apparatus some disturbing effects originating in the operator should be suppressed 
artificially. For this purpose additional optical magnification can be used to enable a 
higher visual perception, and a well defined standard input (target) in order to avoid any 
misinterpretation. 
The input should be representative of the cartographic plotting. Cartographically 
idealised figures are compositions of differential line elements, so called elementary sym 
bols. They can be approximated geometrically by: 
the Fourier analysis, and transformed into the frequency spectrums in at least two 
preferably perpendicular directions, 
the arcs of circles which fit the curvatures of the symbols. 
The losses in the output due to the disturbing effects in the dynamic process are 
expressed in the first case as distortions in undulations, while in the second case as distor 
tions in curvatures. 
For the Fourier analysis the sinusoidal input is specially convenient because it 
represents its elementary unit. If the sinusoidal input is presented to the dynamic system,