Geo-referenced orthophotos of the Salcha River, Alaska, acquired July 25, 2019
Dates
Acquisition
2019-07-25
Publication Date
2021-02-11
Citation
Legleiter, C.J., and Kinzel, P.J., 2021, Field measurements of flow depth and optical image sequences acquired from the Salcha River, Alaska, on July 25, 2019: U.S. Geological Survey data release, https://doi.org/10.5066/P9S4T8YM.
Summary
This data release consists of a set of tiled orthophotos of the Salcha River in Alaska acquired on July 25, 2019. The orthophotos were produced from images obtained using a Hasselblad A6D-100C 100 megapixel digital mapping camera deployed within a pod mounted on the landing gear of a Robinson R44 helicopter. Images were acquired as the helicopter transited a series of flight lines designed to provide complete coverage, with ample overlap, of the study area along the Salcha River. Also within the pod was an ATLANS GPS/Inertial Motion Unit (IMU) that recorded the position and orientation of the platform during the flight. This information was used to geo-reference the images by performing aerial triangulation and bundle adjustment [...]
Summary
This data release consists of a set of tiled orthophotos of the Salcha River in Alaska acquired on July 25, 2019. The orthophotos were produced from images obtained using a Hasselblad A6D-100C 100 megapixel digital mapping camera deployed within a pod mounted on the landing gear of a Robinson R44 helicopter. Images were acquired as the helicopter transited a series of flight lines designed to provide complete coverage, with ample overlap, of the study area along the Salcha River. Also within the pod was an ATLANS GPS/Inertial Motion Unit (IMU) that recorded the position and orientation of the platform during the flight. This information was used to geo-reference the images by performing aerial triangulation and bundle adjustment within the TerraSolid software suite, which was also used to produce a LiDAR DEM that was incorporated into the orthophoto production process. The resulting orthorectified images had a spatial resolution (pixel size) of 0.05 m and were organized into a set of eight 500 m X 500 m tiles. The individual tiles are saved as GeoTIFF files with an embedded header that contains the spatial referencing information for each image; the projected coordinate system is UTM Zone 6N, NAD83. The collection of GeoTIFF tiles is contained within a zip archive. The main purpose of these orthophotos was to serve as a base for geo-referencing videos described in a related data release accessible from the parent landing page cited above.
Click on title to download individual files attached to this item.
SalchaOrthoMetadata.xml “Metadata describing the data and how the data were acquired and processed” Original FGDC Metadata
View
14.95 KB
application/fgdc+xml
“Zip archive containing orthophoto tiles in GeoTIFF format.”
1.35 GB
application/zip
SalchaOrthoPreview.jpg “Preview of tiled orthophoto mosaic of the Salcha River, Alaska.”
117.22 KB
image/jpeg
Related External Resources
Type: Related Primary Pubication
Legleiter, C. J., & Kinzel, P. J. (2021). Improving Remotely Sensed River Bathymetry by Image-Averaging. Water Resources Research, 57(3), e2020WR028795. https://doi.org/10.1029/2020WR028795
For questions concerning this data set, please contact:
Dr. Carl J. Legleiter - cjl@usgs.gov, 303-271-3651
Geomorphology and Sediment Transport Laboratory
United States Geological Survey
4620 Technology Drive, Suite #400
Golden, CO 80403
Purpose
The main purpose of these orthophotos was to serve as a base for geo-referencing videos described in a related data release accessible from the parent landing page cited above.
Rights
Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Preview Image
Preview of tiled orthophoto mosaic of the Salcha River, Alaska.