Method 3
. Read x and y-coordinates at point A.
. For point B proceed as under 1. Determine As
and s numerically.
. Compute Abx according to
A
Abs = = (bxs + (56 + f) (pa—p5))
and set it on the instrument.
. Calculate Aby and Abz according to
A
Aby ==> + (bys + (56 + ) (00)
A
Ahr = T {hs | 4085 (atop)
and set it (the index s stands for the reading taken
at the instrument dials).
. Set vertical control point À and determine z-
coordinate.
. Set vertical control points B and C.
. Compute dE according to
AÂzc—a (x8—x a) — Ann—A (xc—xa)
(xc—x4) (yna—yA) — (xn—x4) (yc—y A)
and introduce it on the individual w-controls of
the instrument.
sz
. From the measurements at A, B and C compute
An according to
due Mech m y — dines ova)
uà (xc—x4) (ya—y 4) — (xs—x4A) (yec—y 4) e
and set it with identical amounts at 94 and gs.
. Compute 4bz according to
An
Abz = — (bxs + (56 + f) (pa—ps))
and set it on the instrument.
Cardan point K as referred to the z-side image plane
in the Planimat is defined by the values
e — 402.5 mm
a= 56.0 mm.
For numerical relative orientation by the least
squares method the following procedure is recom-
mended:
a) After a first empirical orientation determine
the residual parallax P, to Pg at the points 1 to 6
with the aid of the by-screw. The corrections to be
applied to the orientation elements may then be
calculated from the following formulas, where b is
the base line on the ground and at the same time
the distance between the points 3, 4 or 5, 6 and
the base line in the y-direction:
2 (0, +P, +P, +P,
dwa = d TUS —— —(P, - P9] e
Z
dpa = 2b? Pı— Br Pa Pa) Q
1
dæa = 3b (D, —P. PP PS—Pjo
dwa
dbz 7 D Pa + 1025 (1)
2b 0
P P,), (2h d
dy e Git, (664-1 7^
3 3z 0
The dby-value will, however, not generally be
calculated, but only determined empirically.
b) More practical and rapid is the following
method in which vertical parallax at the points 1 to
4 is carefully cleared with the elements indicated in
Table 1, the residual parallax being measured in
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