Equipment Description: The TOAD is a camera sled based on the Guildline MiniBat model 8820 tow body. The frame was configured with a single Sony DCR-PC110 Digital Video Camera in a modified Gates underwater housing, a Canon Power Shot G1 Still Camera (modified by CRED engineers) in an Ikelite housing rated to 60 m slaved to an Ikelite DS-50 strobe, and two 500 W DeepSea Power & Light model 710-0400601 underwater lights. The Canon camera had a custom-built timer that enabled the user to select a constant time interval (ranging from approximately 5 seconds to 2 minutes) between photographs. An interval of 30 seconds was typically selected, which, assuming a mean velocity for the camera sled of 1.5 knots, resulted in one photograph approximately every 20 m. Photograph resolution is 2048 x 1536 pixels and file names are assigned sequentially and automatically by the camera, starting at 100-0000 after the camera's memory is cleared. The MiniBat pressure sensor and wing controller were also mounted on the frame but the pressure sensor was not operational. The cable between the sled and the surface was an underwater load-bearing electrical cable. The TOAD computers were located in the Electronics Lab of the Townsend Cromwell. The electronics box containing the power switches was secured to the ship's fantail, and all other TOAD surface components were secured in the ship's wet lab.
Name & address of person collecting data: Joyce Miller & Ronald Hoeke NOAA IRC NMFS/PIFSC/CRED 1845 WASP Blvd., Building 176 Honolulu, HI 96818
Data Files: Video data were recorded on two video tape recorders. Still photos were recorded on digital camera and downloaded to the TOAD computer after the tow. The position of the camera sled was recorded using Guildline MiniBat In-Tow data acquisition software.
File naming convention: Each tow is given a name consisting of a 3-letter designator for the island area followed by a tow number. During TC0111 the consecutive numbers started at 0006. Video tape labels, the navigation files (*.glo) and paper log forms are all annotated with the tow name. Metadata were extracted from the navigation data and recorded to a file with the same name as the navigation file except that a file type of .met was appended; for example, FFS01106.glo.met
Time Correlation: All times are based on UTC. Two clocks were set manually synchronized prior to starting data collection; the clock in the video character generator that was used to annotate the video tape and the TOAD data acquisition computer clock was used to annotate the navigation (*.glo) files. These clocks were set to UTC at the beginning of each evening's operations and then compared to one another prior to (and during) each tow. There were problems maintaining synchronization of the TOAD computer clock during this cruise. See the problems section for a description.
Resource Description: Digital video images geo-referenced to navigation files
Online Links:
Benthic Habitat Mapping Group, Coral Reef Ecosystem Division (CRED), Pacific Islands Fisheries Science Center (PIFSC), National Oceanic and Atmospheric Administration (NOAA)
This data provides optical observations that will be correlated with bathymetry and acoustic backscatter imagery to develop a benthic habitat map of French Frigate Shoals. Refer to supplemental information for description of instrument and survey.
Are there legal restrictions on access or use of the data?Access_Constraints: None.
Use_Constraints:Please acknowledge the NOAA Coral Reef Ecosystem Division, Pacific Islands Fisheries Science Center as the source of this information.
These data are not to be used for navigational purposes. NOAA makes no warranty regarding these data, expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA cannot assume liability for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to function on a particular system.
| Data format: | Each comma-delimited record contains year, day of year, time, latitude longitude, velocity north and east, water column depth, vehicle depth, layback, and wing angle. For this dataset the fields for vehicle depth and wing angle do not contain useful data. List of navigation files: FFS01106.glo FFS01107.glo FFS01108.glo in format ASCII |
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| Media you can order: | CD-ROM (format ISO 9660) |
| Data format: | List of video tapes: FFS01108, VHS, Master FFS01108, Mini DV, Master FFS01108, Mini DV, Backup in format mini digital video and VHS |
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| Media you can order: | Video cassette tape (format VHS, Mini DV) |
| Data format: | 390 still images available; poor photos were enhanced or deleted List of photo folders: FFS01106: FFS_111201_0724 (97 photos) FFS01107: FFS_111301_0352 (173 photos) FFS01108: FFS_111401_1835 (120 photos) in format JPG digital still photo |
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| Media you can order: | CD-ROM (format JPEG) |