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Navigation Data

Best attempts were made to set the camera to UTC time before the flight. Navigation files (one per day) were created upon returning to the office. Due to equipment restrictions by the USCG, no GPS data were collected during the flight. Image positions were post-processed using two previous flights, May 2008 and May 2009, by matching image features and assigning the GPS location of the previous flight's image to the corresponding image from this flight. Matches were made along the coast approximately every one to two minutes of flight time. The time of capture (timestamp) for each image was recorded in the image header during the flight. Based on the timestamp from the camera, a time was assigned to each GPS location, and then the estimated GPS track for the whole flight was calculated at a resolution of one position per second per record. The positions of the remaining images were then interpolated to give the best GPS position for each image. These values were entered into a spread sheet using Microsoft Excel 2011.

Images were acquired using a Nikon D1X camera. The camera's internal clock was synchronized to UTC. Time was recorded in the EXIF header of each image. Image files are named according to the time they were captured. The image file name has the format yyyy_mmdd_hhmmssd.jpg (for example, image 2009_1204_133636d.jpg was taken December 4, 2009, at 13:36:36 Universal Time Coordinated (UTC), while "d" designates a digital camera was used.)

Processed Navigation

The processed navigation file can be accessed from within the nav folder or by clicking the following link: ds930_09ach03.csv (CSV file). The file contains 12 fields that are defined as follows:

Estimated Navigation

Navigation files (one per day) were created upon returning to the office (see above).

The raw navigation files can be accessed from within the nav folder or by clicking the following link: ds930_09ach03_1204_estimatedGPS.txt (text file).

Field 1: LATITUDE - latitude (decimal degree) position of aircraft
Field 2: LONGITUDE -longitude (decimal degree) position of aircraft
Field 3: HHMMSS - hour minute, second of position (estimated)
Field 4: MMDD - month and daythe photo was taken
Field 5: YYYY - year the photo was taken