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Ann M. Foster; John Jones
The earliest known aerial photographs, from the mid to late 1920s, and resulted in the production of T-Sheets (Topographic Sheets) for the coasts and shorelines of south Florida. The T-Sheets are remarkably detailed, delineating features such as shorelines, ponds, and waterways, in addition to the position of the boundary between differing vegetation communities. If followed through time changes in the position of these ecotones could potentially be used to judge effects of changes in the landscape of the Everglades ecosystem, providing a standard by which restoration success can be ascertained.
The overall objective is to create a digital archive of historical aerial photographs of Everglades national park and surrounding area of the greater Everglades and south Florida. The archive will be in readily available Geographic Information System formats for ease of accessibility. Each set of photos will be broadly disseminated to client agencies, academic institutions and the general public via Open-File Reports and through the Internet.
Neidrauer, C. J.; Johnson, R. A.; MacVicar, T. K.; Perkins, W. A.
S. M. Davis and J. C. Ogden, editors
Gunderson, L. H.; Park, W. A.; Richardson, J. R.; Mattson, J. E.
S. M. Davis and J.C. Ogden, editors
Havens, K. E.; Carrick, H. J.; VanZee, R.
J. W. Porter and K. G. Porter, editors
Foster, Ann M.; Briere, Peter R.; Jones, John W.; Van Arsdall, Carson
Foster, Anne M.; Briere, Peter R.; Coffin, Alisa W.; Jones, John W.; Van Arsdall, Carson; Frye, Laurinda J.
Tiling-Range, G.; Jones, J.; Nelson, P.; Foster, A.; Balentine, K.
Chapter 16 in Landscapes Through the Lens: Aerial Photography and Historic Environment, D. C. Cowley, R. A. Standring, and M. J. Albicht, eds; posted on SOFIA with permission
Areas 1-7 and 10 contain mosaic sheet images only, no over-flight images are available for viewing. Of the 1401 images known to have existed in the 1940s set of aerial photographs, only 920 distinct images were located and scanned. Of these 793 were rectified and 127 were not rectified. See tables at <https://sofia.usgs.gov/exchange/aerial-photos/40s_method.html> for a list of photos not rectified and the problems preventing rectification. Of the rectified photos 79 images were not used due to protocol violations shown at <https://sofia.usgs.gov/exchange/aerial-photos/40s_method.html>
Photographs were scanned using UMAX Mirage II Scanner: Scan resolution of optical 800 dpi; final radiometric resolution of 8-bit per channel; true color (RGB) compatibility; TIFF format output. Two images which were inadvertently scanned as grayscale are noted in the 'oddities' section at <https://sofia.usgs.gov/exchange/aerial-photos/40s_method.html>
Scanned images were rectified using Erdas Imagine 8.7. The rectification process followed protocol developed in house and described in the report 'Guidelines for quality checking of digital ortho imagery, Issue 2.0.' Images were rectified with image to image rectification, using basemaps derived from digital orthophoto quarter quadrangles (DOQQs). The DOQQs were from a statewide set flown in 1995 and available for download from the Florida Department of Environmental Protection Land Boundary Information System (LABINS) website. These images were mosaicked into basemaps of four quadrangles, resampled to 2 meter pixel resolution and reprojected as UTM Zone 17 North. For a few images, the 1995 basemap images were unavailable or unusable and were rectified to a 1999 DOQQ. These are listed in the 'oddities' section.
To register the historic images, a first-order polynomial geometric model was used. Due to a variety of possible factors, such as the age and warping of the original media and irregularities of the camera (about which we had no information) or the flight, we found that a second-order polynomial model improved overall edge matching in some cases. Those images that used a second order polynomial geometric transformation model are listed in the 'oddities' section.
Operators manually selected 10 to 15 tie points per image scattered evenly throughout the image. In some cases additional tie points were subsequently added automatically using the prediction function of Imagine. In all cases the total RMSE for the transformation model was well below a threshold of 0.25. Following the selection of tie points, images were resampled to 1 meter pixel resolution using a bilinear interpolation method. The resulting image was checked with respect to edge matching in a geographic data viewer (ESRI ArcMap 8.3).
Once the operator was satisfied the image was properly registered and appeared to match up with its neighbors, the edges of the image were cropped using a subset function. All images, with the exception of 3 (listed in the 'oddities' section were subset to a square of 7500 pixels and saved in their final file format as geotiff files.
Oddities: There are 1401 images that were known to have existed in the 1940s set of aerial photography. Of these, we were able to locate and scan 920 distinct images. Of these images, we were able to rectify 793 images.
The mentioning of specific software brands or registered trademarks does not constitute a commercial endorsement; their mention is done for clarity only. Mention of software products in the description of graphic processing techniques should be viewed as a use of available tools and not a recommendation for a software product.
The map is available as 8.0" x 9.92" or 26.89" x 33.33" size.
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