Metadata: Identification_Information: Citation: Citation_Information: Originator: Joshua B. Logan Originator: Amy E. East Publication_Date: 20230111 Title: Aerial imagery from the UAS survey of the Los Padres Reservoir delta, Carmel River valley, CA, 2017-11-01 Geospatial_Data_Presentation_Form: JPEG Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9J9CHOH Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, California Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9J9CHOH Online_Linkage: https://www.sciencebase.gov/catalog/item/6378191cd34ed907bf701a6c Larger_Work_Citation: Citation_Information: Originator: Joshua B. Logan Originator: Amy E. East Publication_Date: 2023 Title: Aerial imagery and structure-from-motion data products from a UAS survey of the Los Padres Reservoir delta, Carmel River valley, CA, 2017-11-01 Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9J9CHOH Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9J9CHOH Online_Linkage: https://www.sciencebase.gov/catalog/item/63728580d34ed907bf6c6a0f Description: Abstract: This portion of the data release presents the raw aerial imagery collected during the unoccupied aerial system (UAS) survey of the Los Padres Reservoir delta, Carmel River valley, CA, 2017-11-01. The imagery was acquired using a Department of Interior-owned 3DR Solo quadcopter fitted with a Ricoh GR II digital camera featuring a global shutter. The camera was mounted using a fixed mount on the bottom of the UAS and oriented in an approximately nadir orientation. A total of six flights were conducted for the survey between 19:35 and 22:15 UTC (12:35 and 15:15 PDT). Only the imagery from fights F03 and F06 were used for data processing and are included in this data release. All flights were conducted at an approximate altitude of 100 meters above ground level resulting in a nominal ground-sample-distance (GSD) of 2.6 centimeters per pixel. Before each flight, the camera's digital ISO, aperture, and shutter speed were adjusted for ambient light conditions. For all flights the camera was triggered at 1 Hz using a built-in intervalometer. After acquisition, the images were renamed to include flight number and acquisition time in the file name. The coordinates of the approximate image acquisition locations were added ('geotagged') to the image metadata (EXIF) using the telemetry log from the UAS onboard single-frequency autonomous GPS. The image EXIF were also updated to include additional information related to the acquisition. The data release includes a total of 1,033 JPG images. Images from takeoff and landing sequences were not used for processing and have been omitted from the data release. To facilitate bulk download, the images from each flight are provided in a zip file named with the flight number. In addition to the provided zip files, the images are also available for browsing and individual download on the USGS Coastal and Marine Hazards and Resources Program Imagery Data System at the following URL: https://cmgds.marine.usgs.gov/idsviewer/data_release/10.5066-P9J9CHOH. Purpose: These data are intended to be used to characterize the position, elevation, volume, and morphology of the Los Padres Reservoir delta sediment where the Carmel River enters the reservoir. This assessment of reservoir sediment was made in response to the 2016 Soberanes Fire in the upper Carmel watershed, followed by high flows during water year 2017. Supplemental_Information: Additional information about the field activity from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-635-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20171101 Currentness_Reference: ground condition at time data were collected Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -121.6669 East_Bounding_Coordinate: -121.6620 North_Bounding_Coordinate: 36.3805 South_Bounding_Coordinate: 36.3737 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: elevation Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:6378191cd34ed907bf701a6c Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: Bathymetry and Elevation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: topography Theme_Keyword: topographic maps Theme_Keyword: remote sensing Theme_Keyword: geomorphology Theme_Keyword: aerial photography Theme_Keyword: image mosaics Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: photography Theme_Keyword: remote sensing Theme_Keyword: aerial and satellite photography Theme_Keyword: altimetry Theme_Keyword: orthophotography Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CHMRP Theme_Keyword: Pacific Coastal and Marine Science Center Theme_Keyword: PCMSC Theme_Keyword: UAS Theme_Keyword: Unmanned aerial system Theme_Keyword: Structure-from-motion Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: State of California Place_Keyword: Carmel River Place_Keyword: Monterey County Access_Constraints: None Use_Constraints: USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/item/6378191cd34ed907bf701a6c?name=F03_20171101T201600Z_RB000858_browse.jpg&allow=openTrue Browse_Graphic_File_Description: Example aerial image from 2017-11-01 UAS survey. Browse_Graphic_File_Type: JPEG Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The Ricoh GR II cameras used to acquire these images produce a nominal image size of 16.2 megapixels in both JPG and camera raw (Adobe DNG) image formats. The image acquisition time stamp is recorded to the image metadata (EXIF) with a precision of 1 second. The UAS onboard GPS is a single-frequency autonomous receiver which records positions to the telemetry log at 1 second intervals, with an approximate accuracy of 3 meters horizontally and 10 meters vertically. The geotagging operation uses the image time stamp to derive the image acquisition location by finding the nearest location recorded at the time of acquisition. To reduce the potential for timing errors during the geotagging process, the image time stamps were adjusted to true ('corrected') UTC time by comparing the image time stamps with several images taken of a smartphone app ('Emerald Time') showing accurate time from Network Time Protocol (NTP) servers. For this survey, +00:00:01 (1 second) was added to the image time to synchronize with corrected UTC time. The adjusted time stamp was only used for geotagging; the original image time stamp was retained in the image EXIF and file name. The positions stored in the EXIF are in the WGS84 (G1150) coordinate reference system (EPSG:4979), with elevation in meters relative to the WGS84 ellipsoid. Logical_Consistency_Report: Photographs were renamed using a custom python script to include flight number, image acquisition date and time in Universal Coordinated Time (UTC), camera ID, and original image ID number. The image EXIF were also updated to include additional information related to the acquisition. Some photographs may be auto-rotated by certain viewing software, but the original image orientation is the same for all images. Completeness_Report: Six flights (F01, F02, F03, F04, F05, and F06) were conducted during the survey. The imagery from each flight was stored separately, and the flights were renamed for organizational purposes. The camera shutter was triggered at 1 Hz by a built-in intervalometer which was started before takeoff and stopped after landing. On flight F01 and F04 no imagery was collected. During flight F02 the camera battery discharged during the flight, shutting the camera down. Only the imagery from flights F03 and F06 were used for processing and map production, and only imagery from those flights is included in this data release. Images from the takeoff and landing sequences were not used in data processing and are not included in this data release. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The horizontal positions stored in the EXIF image metadata were derived with a 'geotagging' process using the image time stamps and the uncorrected positions recorded in the telemetry log of the UAS from the onboard single-frequency autonomous GPS (mRobotics GPS u-Blox Neo-M8N / 3DR SOLO Upgrade). To reduce the potential for timing errors during the geotagging process, the image time stamps were adjusted to true ('corrected') UTC time by comparing the image time stamps with several images taken of a smartphone app ('Emerald Time') showing accurate time from Network Time Protocol (NTP) servers. The horizontal positions are estimated to be accurate to approximately 3 meters. However, it should be noted that for some images the error may exceed this estimate due to GPS errors or timing errors associated with the geotagging process. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The vertical positions stored in the EXIF image metadata were derived with a 'geotagging' process using the image time stamps and the uncorrected positions recorded in the telemetry log of the UAS from the onboard single-frequency autonomous GPS (mRobotics GPS u-Blox Neo-M8N / 3DR SOLO Upgrade). To reduce the potential for timing errors during the geotagging process, the image time stamps were adjusted to true ('corrected') UTC time by comparing the image time stamps with several images taken of a smartphone app ('Emerald Time') showing accurate time from Network Time Protocol (NTP) servers. The horizontal positions are estimated to be accurate to approximately 10 meters. However, it should be noted that for some images the error may exceed this estimate due to GPS errors or timing errors associated with the geotagging process. Lineage: Process_Step: Process_Description: Aerial imagery was collected using a Department of Interior-owned 3DR Solo quadcopter fitted with a Ricoh GR II digital camera featuring a global shutter. The camera was mounted using a fixed mount on the bottom of the UAS and oriented in an approximately nadir orientation. During acquisition the UAS was flown on pre-programmed autonomous flight lines at an approximate altitude of 100 meters above ground level (AGL), resulting in a nominal ground-sample-distance (GSD) of 2.6 centimeters per pixel. The flight lines were spaced to provide approximately 70 percent overlap between images from adjacent lines. The camera was triggered at 1 Hz using a built-in intervalometer. Before each flight, the camera's digital ISO, aperture and shutter speed were manually set to adjust for ambient light conditions. Although these settings were changed between flights, they were not permitted to change during a flight; thus, the images from each flight were acquired with consistent camera settings. Process_Date: 20171101 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Joshua Logan Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Country: US Contact_Voice_Telephone: 831-460-7519 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: jlogan@usgs.gov Process_Step: Process_Description: The image files were renamed using a custom python script. The file names were formed using the following pattern Fx-YYYYMMDDThhmmssZ_Ryz.*, where: - Fx = Flight number - YYYYMMDDThhmmssZ = date and time in the ISO 8601 standard, where 'T' separates the date from the time, and 'Z' denotes UTC ('Zulu') time. - Ry = RA or RB to distinguish camera 'RicohA' from 'RicohB' - z = original image name assigned by camera during acquisition - * = file extension (JPG) The approximate image acquisition coordinates were added to the image metadata (EXIF) ('geotagged') using the image timestamp and the telemetry logs from the UAS onboard single-frequency 1-Hz autonomous GPS. The geotagging process was done using the Geosetter software package. To improve timestamp accuracy, the image acquisition times were adjusted to true ('corrected') UTC time by comparing the image timestamps with several images taken of a smartphone app ('Emerald Time') showing accurate time from Network Time Protocol (NTP) servers. For this survey, + 00:00:01 (1 second) was added to the image timestamp to synchronize with corrected UTC time. The positions stored in the EXIF are in geographic coordinates referenced to the WGS84(G1150) coordinate reference system (EPSG:4979), with elevation in meters relative to the WGS84 ellipsoid. Additional information was added to the EXIF using the command-line 'exiftool' software with the following command: exiftool ^ -P ^ -IPTC:Credit="U.S. Geological Survey" ^ -IPTC:Contact="pcmsc_data@usgs.gov" ^ -EXIF:Copyright="Public Domain" ^ -XMP:UsageTerms="Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty." ^ -EXIF:ImageDescription="Low-altitude aerial image of the Los Padres Reservoir delta area, Carmel River valley, California, USA, from USGS field activity 2017-635-FA; https://cmgds.marine.usgs.gov/fan_info.php?fan=2017-635-FA" ^ -XMP:Event="Unoccupied Aircraft System survey of Los Padres Reservoir delta area during USGS field activity 2017-635-FA." ^ -EXIF:GPSAreaInformation="Position from UAS onboard autonomous single-frequency GNSS." ^ -EXIF:GPSMapDatum="EPSG:4979 (WGS 84)" ^ -EXIF:Artist="U.S. Geological Survey, Pacific Coastal and Marine Science Center" ^ -IPTC:CopyrightNotice="Public Domain. Please credit U.S. Geological Survey." ^ -IPTC:Caption-Abstract="Aerial image of the Los Padres Reservoir delta area and Carmel River, Carmel River valley, California, USA, from an Unoccupied Aircraft System (UAS) during USGS field activity 2017-635-FA." ^ -sep ", " ^ -keywords="Carmel River, Los Padres Reservoir, Monterey County, California, 2017-635-FA, Unoccupied Aircraft System, UAS, drone, aerial imagery, U.S. Geological Survey, USGS, Pacific Coastal and Marine Science Center" ^ -comment="Aerial image of the Los Padres Reservoir delta area and Carmel River, Carmel River valley, California, USA, from an Unoccupied Aircraft System (UAS) during USGS field activity 2017-635-FA."^ -Orientation= ^ -XMP:AttributionURL="https://doi.org/10.5066/P9J9CHOH" ^ -OffsetTime*=+00:00 -AllDates+=7 ^ -r f* ^ -ext DNG ^ -ext JPG Additional metadata tags were populated in the imagery metadata using the following command: exiftool ^ -P ^ "-XMP-photoshop:Credit