GISCafe Guest 
Roger Thomas
As a recently qualified Land Surveyor, Roger joined an aerial survey and mapping company based in the UAE in the late 70s. Working with the company over the next three decades, progression was made from the management of the Survey Deportment to overall Operations Manager and culminated in Project … More » NETROnline completes scanning of the challenging first half of the Edgar Tobin Aerial Survey film archive using GeoDyn’s PromptScanOctober 3rd, 2024 by Roger Thomas
NETROnline, the producers of www.historicaerials.com, have successfully completed the scanning of the first half of the 1.2 million frames of the Tobin aerial film archive that dates back to the 1930’s. This archive documents in detail the massive changes that took place across the southern United States during the first half of the 20th century.
The scanning was performed using GeoDyn’s PromptScan M2 photogrammetric scanner. To date, NETROnline has scanned over 600,000 frames at a resolution of 13 microns, accurately capturing and preserving the full detail from this important archive. The initial phase of the project has been the most challenging as it included many rolls of film from the 1930’s that are primarily nitrate-based, as well as over thousand frames that had been previously cut out of the rolls and which required careful handling. Without scanning, these films would soon have deteriorated beyond scannable condition, risking a significant heritage loss.
Scanning represents just the initial phase of the process. To fully leverage scanned imagery, the imagery needs to be georeferenced and then accurately orthorectified. This was also a very significant challenge, as only a few of the original flight records existed and those that did, were sketches drawn by navigators often flying in wooden biplanes. Finding even the approximate location of the images across the southern US for a terrain that has changed beyond recognition, has been an immense challenge..
NETROnline is utilising GeoDyn’s PromptGeoref service to enable georeferencing, aerial triangulation and accurate orthorectification of the imagery. These services include extensive machine learning assisted searches to identify the possible image locations and then identification of the very few locations that had not changed. The processes then use ArcGIS based aerial triangulation and orthorectification procedures to create the seamless orthoimage mosaics that form temporal basemaps. These can be used to quickly identify what was where and when, determine change, and identify trends. “We are proud to partner with NETROnline on this groundbreaking project,” said Roger Thomas , GM at GeoDyn. “The successful completion of digitizing such a vast collection of historical aerial images underscores our commitment to providing cutting-edge solutions that meet the evolving needs of archival preservation.”
For more information about GeoDyn’s advanced scanning and georeferencing solutions, visit www.geodyn.com About GeoDyn GeoDyn provides full-service aerial film conversion and rapidly digitizes films using advanced PromptScan photogrammetric aerial film scanners. Highly automated processes then accurately georeference the imagery to create temporal ortho image basemaps and oriented imagery that can be efficiently served, visually interpreted and analyzed in ArcGIS. As an Esri Gold Partner, GeoDyn assures full integration with ArcGIS. About NETROnline Historic Aerials by NETROnline (owned by NETR) is a comprehensive platform offering access to public records across the United States, specializing in property records, deeds, and mortgages. Beyond standard records, it features a unique repository of historical aerial imagery, enabling users to explore changes in landscapes and properties over time, making it a valuable resource for researchers, analysts and historians alike. |
|
|
|||||
|
|
|||||
|
|||||
