Low-altitude aerial imagery collected from a Helikite at Head of the Meadow Beach, Truro, MA on March 20, 2024

These JPEG images were collected with a camera (Sony a6000) hung from the Helikite via a Go-Pro mount (2024-011-FA_HOM_imagery_browse.JPG) so that the camera faced downward and towards the bluff at about 40 degrees. The Helikite was on a 60 m string and kitesurfing harness; together the Helikite and gear were walked up and down the beach to achieve overlapping images taken every 5 seconds.

The images acquired with the camera were geotagged and processed to add additional information required by the USGS to the EXIF headers using ExifTools (https://exiftool.org/, version: 12.06), and the files were renamed to a unique identifier using Namexif (http://www.digicamsoft.com/softnamexif.html, version 2.1) to avoid any possibility of duplicate names. These steps are described here. For more information on the EXIF tags here and automatically populated by the camera see https://exiftool.org/TagNames/EXIF.html
1. The horizontal positions and elevations of each image (2024-011-FA_HOM_photoLocations.csv) are from the estimated locations in the Metashape project that was reconstructed using structure from motion based on the images and AeroPoints (see larger work citation). ExifTools was used to tag each photo with the following tags: Credit, Copyright, UsageTerms, ImageDescription, Artist, XMP:ExternalMetadataLink, XMP:UsageTerms, XMP:AttributionURL, XMP:PreservedFilename, GPSTimeStamp, GPSAltitudeRef, GPSLatitudeRef, GPSLongitudeRef, GPSAreaInfo, GPSMapDatum, GPSLatitude, GPSLongitude, and GPSAltitude stored in a CSV file with the command:' -exiftool -csv="C:\directory\name\Geotags_EXIF.csv" C:\directory\name\of\photos *.JPG
The first row of the CSV are the tag names; the first column is SourceName (unique image names).
To read out the photo information to a CSV when in the directory with the photos the command is: exiftool -csv *.JPG > directory/name/allheaders_out.csv
2. All the JPEG images were renamed with Namexif (https://us.digicamsoft.com/softnamexif.html v 2.2 accessed April 2020) to ensure unique filenames and compliance with the USGS Coastal and Marine Hazards and Resources Program's best practices for image naming convention. Images were renamed with the field survey ID prefix; flight number, and ID that distinguishes USGS cameras by make/camera number, the image acquisition date, coordinated universal time (UTC) in ISO8601 format, and a suffix with the original image name. For example, image name '2024011FA_f01s6000_20240320T165822Z_image####.jpg', 2024011FA is the survey ID, f01 is the flight number, s6000 is the camera make (SONY) and model (6000), and 20240320 is the UTC date in the format YYYYMMDD. A 'T' is used to separate UTC date from UTC time in format HHMMSS followed by a Z, and image####.jpg is the original raw photo name appended to the end of the new filename.