CIPA 2003 XIX th International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
3. FIELD SURVEY 
In all building surveys, 3d object information is reduced to a 
minimum of points. From those points, a data structure with 
predefined geometrical elements can be derived. In this 
research, point coordinates were derived through total station 
measurements and multi-image photogrammetry. Total station 
measurements have supplied control point information. Multi 
image technique has been applied while taking metric images. 
This has provided ease in selecting camera positions. In addition 
to these two surveys, digital images were taken for producing 
the texture of the building model. The process of the field 
survey is explained in the below under two headings: 
measurement of control points and image acquisition. 
3.1 Measurement of Control Points 
All elevations were surveyed with total station. It was decided 
to measure minimum six evenly distributed points for every 33 
by 14 meters. In other words, the long elevations were divided 
into three measurement areas and the short ones were 
considered as single measurement areas. Then, a polygon was 
inserted around the building (Figure 2). The control points on 
the elevations were connected to the polygon through a series of 
measurements, x, y and z values for each selected point were 
measured. All this measurement process included the facade 
area up to the entablature zone. The recessed roof portion was 
eliminated. 
3.2 Image Acquisition 
In this step, criteria for selecting metric and digital cameras, and 
taking photographs were developed. 
3.2.1 Camera Selection: A comparison of image formats 
and resolution after film-scanning presents that medium format 
metric cameras are the best ones suitable for building 
recording (Pomaska, 1998). Image formats in the range of 
60mm x 60mm are known as medium format cameras. Such 
cameras provide metric solutions using a reseau. The widest 
known metric camera for close range applications is the 
Rolleiflex 6008 metric. It is a reseau camera with 121x121 
crosses; mesh distance 5mm. This camera is the ideal solution 
for photogrammetry in cultural heritage recording (Pomaska, 
2001). On the other hand, digital cameras are time saving 
devices for detailing the building models produced on the basis 
of surveys with metric cameras (Grussenmeyer, et all, 2002). 
Digital cameras are still in a rapid development process. 
Today, digital cameras known as SLR (Kodak Blue Plus Color 
Full Frame) are of importance for architectural photogrammetry 
(Pomaska, 2001). 
Figure 2. The polygone and the coordinate system established 
around Defensionskaserne. 
In the case of Defensionskaserne, Rolleiflex 6006 metric 
camera and Kodak DCS 290 are used, respectively. They are 
not the state of art at present, but they were the ones available in 
hand and they are sufficient for the job. Kodak 400 ASA film 
was used. With Rolleiflex 6006, metric recording of the 
building was carried out. Then, the model produced on the basis 
of the data collected with Rolleiflex 6006 is textured by the help 
of digital images taken with Kodak DCS 290. 
3.2.2 Development of a Strategy for Taking Photographs: 
The strategy for taking metric and digital images were 
developed separately. For metric images, it is known that multi 
image technique is easy to handle on site. Camera stations can 
be selected without restrictions. Total station measurements 
supply control point information in a unique coordinate system. 
Complex buildings can be recorded with several separated 
image bundles. 
It was decided to survey only the decorated east elevation of 
Defensionskaserne in detail. This means multi-image technique 
was applied only here. As explained for the control point 
measurements (see section 3.1), this long elevation of nearly 
100m was divided into three parts named as left, middle and 
right. It is known that bundling all the images together should 
be preferred for the success of the adjustment. However, the 
division of the long facade into three parts has some practical 
outcomes. It becomes possible to work on every part separately. 
This means the opportunity of different people working on 
different parts. At the same time, it becomes easier to make the 
bundle adjustment since the number of images is decreased. 
The position and direction of middle format cameras were so 
organized that the facade whole was covered (Figure 3). It was 
important to shoot two images for each building component to 
be measured. A third image was preferred to provide control 
information. While shooting these images that cover up the 
same area to be measured, correct definition of the intersection 
angle between the shooting directions gains importance. That 
means the intersection angle should neither be very acute nor 
obtuse, but it should be around ninety degrees. This angle 
selection does not only goes for xy plane, but also for zy plane. 
At the end of this survey, close up images at human scale and