4. Since compilation of the manuscript has been the most
time consuming operation in photogrammetry, it is generally
considered to be the most profitable for automation. It is
also one of the most intriguing, since this operation demands
that automation make a multitude of decisions for each photo-
graphic pair concerning the intersection of homologous rays
both during orientation procedures and during contouring or
profiling, hopefully, regardless of type of terrain, quality
of photography, or kind of ground features.
5. Contours, which are only a part of the complete
manuscript, are produced automatically either in conventional
form on a coordinatograph or in a line drop output. The latter
is produced while profiling a stereomodel and can take the form
either of oriented line segments, which represent a contour
level, or lines of different densities exposed between contour
levels. An example of the latter type is shown in Figure 1. |
Final contour manuscript must then be constructed manually © | &
by connecting the line segments or drawing the average boundaries |
between bands of different densities.
6. At the present state of automation in photogrammetry,
the orthophoto is the substitute for the planimetric portion
of the manuscript. This term, which is used to define a
photograph having all of its features located in correct posi-
tion or orthographically, is now commonly accepted. The ortho-
photomap, which is an assemblage of orthophotos into a stan-
dard map sheet format with certain important terrain features
intensified for easier identification and with names added,
is gaining acceptance among users and is considered superior
to the standard topographic map for many purposes. If this
is generally accepted, Automation in Photogrammetry will be
responsible for changing, at least partially, the end product
from a topographic map to an orthophotomap. It is not beyond
the realm of possibility that through automation, specifically
automating image extraction from photographs, that line maps
will eventually be compiled as a direct output of automatic i ©
compilation. There are some interesting developments being
conducted along this line which are still many years in the
future and are not within the scope of this paper. At the
present time, the orthophotomap is an intermediate product
when a line map is desired as the end result, and the opera-
tion required to extract mapping detail into line map form is
considered as a cartographic procedure and a candidate for
cartographic automation.
7. Why Automation? As in every other field of endeavor,
automation is attractive because of overall economic considera- |
tions. The performance by machines of operations quicker, with |
less manpower and at a lower cost, is the basic consideration
which determines whether automation will be adopted. Automation
usually has greater reliability because of less dependence on