RECENT DEVELOPMENTS IN DIGITAL PHOTOGRAMMETRIC SYSTEMS FROM LEICA-HELAVA DSW 1 
  
  
  
  
  
  
  
  
  
  
  
Helava 
Alex Dam peak ir 
System Engineer, Helava Associates, Inc., USA PC. At 
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A. Stewart Walker hardwe 
Product Manager Digital Photogrammetry, Leica AG, USA maturi; 
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Commission II, Working, Group II/5 um, bu 
photog 
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KEY WORDS: Digital Photogrammetric Systems, Softcopy, Status, Scanner, Triangulation, DEM/DTM, kept to 
Orthoimage, Feature Extraction. as the 
to the 
altoget 
ABSTRACT contait 
mount: 
Leica digital photogrammetric systems by Helava consist of the new DSW300 Digital Scanning Workstations and the a liveh 
DPW670 and DPW770 Digital Photogrammetric Workstations, which are monoscopic and stereoscopic respectively 
and are offered on a range of hardware platforms. Since the 1992 Congress, these systems have become established as 2.2 Di 
leading, contenders in today's busy market-place. The innovative roll film transport of the DSW300 complements the 
elements of the earlier DSW200 which have been retained owing to their highly satisfactory performance over the past Soon ; 
two years. The scanning software has been extended to include operations for the operation of the roll film as well as perfori 
improvements on the DSW200 functionality. The standard software of the DPWs, SOCET SET®, has undergone a introdi 
host of improvements during the quadrennium and has migrated across a number of hardware platforms, requiring a SPAR! 
diversity of graphics sub-systems for stereoscopic viewing. The major innovations include full 24 bit colour in all increa: 
operations, automated aerial triangulation and much enhanced mosaicking. Equally exciting progress has been made to prc 
on the feature extraction side: several packages are available, including excellent DPW implementations of the well resolu 
known ATLAS and PRO600/MicroStation. Some of these now include automated tools which have been shown not using 
only to give noticeable increases in productivity but also to reduce fatigue. GIS packages available on-line include design 
GeoCity and System 9. The customer base has become exceedingly broad and includes private sector, local and state the co 
government, national mapping and military segments. Commercial pressures have fostered the growth of bureaux stage), 
services, especially for photo processing and scanning, and have encouraged many companies to promote heavily their quality 
digital orthophoto capabilities. The future will feature migration to other popular platforms as well as profound (later 
productivity benefits in feature extraction and project management. Sophis 
nct 
the he 
1. INTRODUCTION projects in the late 1980s. Naturally, the scanners reflect image 
the state of both technology and digital photogrammetry becam 
| Technological improvements and competitive pressures, ^ over the years. The very first, military scanner used a introd 
| coupled with evolving, heavy demands from a linear array, but all subsequent models have been based perfor 
2T knowledgeable and competent customer base, have on area array CCD technology (Table 1). scanni 
| forced development in digital photogrammetry to able 
| proceed apace in a variety of directions. The Leica Model Host Production mappl 
| digital photogrammetric systems by Helava have been [DCCS MicroVAX 1987-91 works 
| successful during the period 1992-96, primarily through HAI-100 $0386 PC 1990-91 buoya 
| sound initial designs for the various product, coupled DSW 100 | 80486 PC 1991-94 : 
| i illingness to respond to change in computer : This 
with uwilfingo ; DSW200 | SPARCstation 208X, 1994-96 
hardware and customers’ needs. These systems are well funda 
documented: the evolution from the military systems of DSW300 x : — e EN 1996 have 
the 1980s has been described by Helava (1991) and Hal Creator v ode - perfor 
Miller, Helava and Devenecia (1992). The status at the : used 
1992 Congress was reported by Miller, Thiede and Table 1. Evolution of the scanners quar 
Walker (1992), with updates by Miller and Walker senst 
(1993, 1995). There is also a wealth of accounts by users. 2.1 HAI-100/DSW 100 (from 
The goal here is to outline the changes during the last impre 
four att but the emphasis is on the features and The CCS NON À D stem for SURE autora d 
0 
bonefité a Imo current systems, DEC MicroVAX host (Helava, 1987), but the first true from 
scanner was the HAI-100, based on an Intel 80386 PC. and s 
2.0 SCANNING RETROSPECTIVE AND UPDATE This performed interior orientation and then resampled area « 
> images rectified to photo space, to facilitate immediate also ; 
The last four years in the image scanner industry have stereoscopic viewing and epipolar correlation processes impre 
been exciting, for both hardware and software. As one of for automatic DTM generation. The scan times were to 1n 
the digital photogrammetric industry leaders, Helava and extraordinarily long (two hours for a 25 um image) by robus 
Leica have been in the forefront of these changes. Helava today’s standards, but that was still fast enough to keep mode 
was an early entrant in the scanner business and is now UP with the competing products since they were slow too array 
entering into the third generation of its scanner product and the image preparation work performed by the HAI- Large 
100 was appreciated by customers. It was renamed the mark 
line, which began as a commercialisation of military 
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B2. Vienna 1996