observed the Swedish system of using control stakes - placed as described in Profes-
sor Hallert's article - before Rosendal Palace which was being recorded and drawn
by photogrammetric procedures, and I respect the accuracy of this method. However,
I have never found, when recording historic American architecture in the centers of
our cities, the situation which would permit the setting up of this auxiliary method of
control. The stereopair of the east facade of Trinity Church in New York City, as
photographed up the length of Wall Street, shows also the extreme base-distance ratios
that may be forced upon the photographer in architectural photogrammetry. (See
Figure 1).
In recording historic architecture the building to be photographed is often
hemmed in by others, and the camera stations are separated from the survey control
points on the building by the rush of city traffic, and there is sometimes haste to take
a stereopair of a facade in the sunlight which may for only a few minutes shine down
the long canyon of a narrow street. The overriding concern is to secure complete
photographic coverage. On one occasion this has taken the phototheodolite onto the
twenty-third floor parapet of a building overlooking the one to be photographed; more
often it has taken the photographic team far up and down the streets that border the
building for angled and inclined views that show it in its full height. The stereopairs
photographed from these angles cannot be oriented efficiently according to the proce-
dures of aerial photogrammetry.
A major characteristic of architecture in contrast to other subjects of the
photogrammetric process is its geometric regularity. Except in the highly interesting
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