Fig. 5 
GIS/VM from Image Interpretation Systems 
The suite of products from Aarau is completed by three devices 
from the Industry and Special Products division. The RK820 
stereoscope has optics of the highest quality and offers a 
magnification of up to 285x for detailed examination of metric and 
reconnaissance photography. The SMI2 stereoscope is designed for 
viewing and measuring several rolls of 70 mm film, whereas the 
Zoom Sight 20x is a simple viewer for single images. In all three 
cases, image quality is very high and image fragments can be 
captured digitally, or simply shown on monitors, by means of CCD 
camera ports, which also accommodate 35 mm or Polaroid cameras. 
The bulk of Leica's photogrammetric activity, therefore, takes 
place in Aarau. Product lines from Heerbrugg, Rochester and 
Solms, however, are important too. 
3.2 Leica Heerbrugg AG 
All photogrammetric products from Heerbrugg are located in the 
Industry and Special Products division. The RC20 aerial camera 
system and TSP1, ST4 and APT2 stereoscopes are familiar to most 
photogrammetrists. Elcovision 10 is a low cost photogrammetric 
measuring system based on the Leica R5 camera (see 3.4 below), 
enlarged paper prints, digitising tablet, Wild software and the 
AutoCAD package. Finally, a tiny proportion of the Wild plotters 
is sold for use in photogrammetry, primarily TAlOs and TA30s. 
3.3 Image Interpretation Systems, Inc. 
The manufacturing unit of Cambridge Instruments located in 
Rochester, New York, is now known as Image Interpretation Systems, 
Inc. The products are well established and popular. Zoom 95, 
Zoom 240 and Zoom 500 stereoscopes have sold in large numbers for 
many years. The ZT-4, ZT4-H and Stereo Zoom Transfer Scopes are 
used in numerous mapping organisations throughout the world to 
transfer photographic information graphically on to maps. The 
ZTS/VM is a Stereo ZTS with the VM Vertical Measurement Module for 
calculating XYZ ground coordinates rigorously. The newest product 
is the GIS/VM, which omits the map superimposition and optics for 
anamorphic geometry from the ZTS/VM, leaving an economical 
instrument designed for data acquisition for input to GIS systems 
with straightforward operating procedures (Fig. 5).