Foster, Anne M., Briere, Peter R., Coffin, Alisa W., Jones, John W., Van Arsdall, Carson, Frye, Laurinda J.
The numbering scheme for the aerial photos is an identification number consisting of the flight number followed by the photo or frame number.
The earliest known aerial photographs are from the mid-to-late 1920s and resulted in the production of what are called T-sheets (Topographic sheeets) for the coasts and shorelines of far south Florida. The position of the boundary between differing vegetationcommunities (the ecotone) can be accurately measured. If followed through time, changes in the position of these ecotones could potentially be used to judge teffects of drainage on the Everglades ecosystem and to monitor restoratio success.
The Florida Integrated Science Center (FISC), a center of the U.S. Geological Survey's (USGS) Biological Resources Discipline (BRD), in collaboration with the Eastern Region Geography (ERG) of the Geography Discipline has created digital files of existing 1940 (1:40,000-scale) Black and White aerial photography for the South Florida region. These digital files are available through the SOFIA web site at <http://sofia.usgs.gov/exchange/aerial-photos/index.html>.
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
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 <http://sofia.usgs.gov/exchange/aerial-photos/40s_method.html>
Scanned images were rectified using Erdas Imagine 8.7. 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.
U.S. Department of the Interior, U.S. Geological Survey, Center for
Coastal Geology
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