Multispectral reflectance imagery collected from an unmanned aerial system over oyster reefs in the Bay of St. Louis near Gulfport, Mississippi from 2018-12-17 to 2018-12-18

This data comprises imagery collected from an unmanned aerial system (DJI M600 Matrice) over oyster reefs in the Bay of St. Louis near Gulfport, Mississippi from 2018-12-17 to 2018-12-18. This dataset was collected with the goal of observing water quality from a remote platform. In particular, the data was collected to see how well it correlates with the hyperspectral imagery collected from the same flights, and to see if the five bands provided can supply enough information to observe relevant phenomena. The imagery was collected using a MicaSense RedEdge sensor, a five-band sensor that produces an image for each band. The bands are blue, green, red, red edge, and near-infrared. Center wavelengths are 475 nm, 560 nm, 668 nm, 717 nm, and 840 nm. The bandwidth for each is 20, 20, 10, 10, and 40 nm, respectively. RedEdge field-of-view (FOV) is 47.9 degrees horizontal, 36.9 degrees vertical. All imagery contains latitude, longitude, and altitude information, along with other camera parameters that allow for imagery post-processing. The processed data has been converted into reflectance values, ranging from what should be 0.0 to 1.0. Due to limitations in the collection and the downwelling light sensor for the RedEdge, these values will be incorrect if the lighting has changed significantly. In general, this will be because of cloud cover. There is a small amount of solar irradiance change as well over the flight, although that change should not heavily impact the data for its intended use. To achieve the reflectance corrections, all images are adjusted for gain, exposure time, vignetting effects, and lens distortion. This code is based on MicaSense's processing tutorials and is available on request. Images are also individually orthorectified. As there are no tie points with which to mosaic the images, a Python script is used to project images individually on a flat surface using the position, altitude, and attitude of the sensor at the time of image capture. This code can also be supplied on request. Related dataset (processed hyperspectral) is available under GRIIDC Unique Dataset Identifier (UDI): MS.x839.000:0020 (DOI: 10.7266/SDX8GEZY).