PA Historical Aerial Photography

Overview

Historic aerial photographs (often called ‘vertical photography’), are some of the most useful, yet frustrating to use print geographic resources because they are very large scale (i.e. they often cover relatively small areas), and lack any labeling to help users orient themselves to the historic landscape that is depicted. What’s more, they lack geographic reference information and contain distortions that limit their use for anything other than qualitative visual comparison. This is in contrast to contemporary orthoimagery from multiple sources (satellites, fixed wing aircraft and UAVs), that have become primary base data sources of geographic information.

We have several on-going projects to:

  1. Inventory the historic aerial photographs that are available in Pennsylvania. See here for a map view of available historic photography for Pennsylvania.
  2. Acquire higher quality digital copies of vertical photography of Pennsylvania than are currently publically available (e.g. these color-infrared photos from the NHAP program, 1947-1952 USDA black and white photos 1:20,000).
  3. Acquire higher quality digital copies of vertical photography of Pennsylvania than are currently publically available (e.g. these color-infrared photos from the NHAP program, 1947-1952 USDA black and white photos 1:20,000).

Our hope is that in the next few years we will begin to produce base data layers of pseudo-orthoimagery for historic time-periods for the state of Pennsylvania.

If you’re interested in these projects, please contact Nathan Piekielek.

People

Nathan Piekielek, Zhiyue Xia, Colin Grube, Miranda Waldman, John (Jack) Swab, Michael Price, Karen Schuckman, Heather Ross, Tara LaLonde, Brittany Waltemate, Jamie Friedken, Kathryn Giesa, Milan Liu, Nicholas Friedken, Thomas Whalon, Zhaogeng Ding

Pennsylvania Aerial Photograph Project: Identification of missing 1970s and 1940s photos and file name updates

Overview

This project involved working with Pennsylvania aerial photos [Penn Pilot (Historical Aerial Photo Library)] available from PASDA.  Over the summer of 2020, missing photographs from the 1940s and 1970s were identified, and some issues with shapefiles and attribute standardization were corrected. The process as a whole required the team to create new shapefiles with the county data, make corrections to the shapefiles, then make updates to them with additional information, and finally review the set to ensure that file names matched. 

Initially, existing data on county photocorners was obtained from PASDA’s directory, and shapefiles were created for counties, including data on name, mission code (reference number ), roll number (camera rolls in order of when they were captured), exposure, date, and the saved filename. Next, these shapefiles were checked for corrections, and photographs that were incorrectly listed were redesignated to the appropriate positions. Various variables such as mission, roll, and exposure were separated using existing separators, and for those elements with no delimiters, the three variables were split manually upon calculating their string lengths. The data collected from  county photocorners was updated with the shapefile corrections. The next step for the team was to parse through the index photographs to determine the dates for individual photographs and update the shapefiles with these dates. Finally, the filenames were checked to see if they matched using an R-Script originally written by Nathan Piekielek with updates from Milan Liu. Corrections were made until all errors in file names were sorted out and the final product of the team’s effort was realized.

Contributors

Brittany Waltemate, Milan Liu, Ben Brosius, Ryan Armani, Ishaan Anavkar, Dan  Valadas, Olivia Neill, Nick Friedken

Nathan Piekielek, Tara Anthony, Jae Sung Kim, Heather Ross