TITLE: UAV - RGB orthomosaic from Röbäcksdalen, north-eastern Sweden.
SITES STATION: Röbäcksdalen Field Research Station
TIMESTAMP: 2022-07-18 11:43 - 2022-07-18 12:07
TIME ZONE: UTC +1
SAMPLING POINT: Centroid of location polygon - Drone area 02 from 2021 
LATITUDE: 63.808814
LONGITUDE: 20.235958
ALTITUDE: 7.2 m a.s.l.

FILE RETRIVED FROM: https://data.fieldsites.se
DATA POLICY: SITES data is licensed under a Creative Commons Attribution 4.0 international license (http://creativecommons.org/licenses/by/4.0/).

PARAMETERS & UNITS: DN (-), H (m), V (m s-1), WS (m s-1)

DESCRIPTION: 
Near-ground RGB orthomosaic generated from a UAV platform, with a RGB camera. Nominal pixel resolution is 5 cm. 
The ecosystem surveyed is an intensively managed pasture (a mix of Phleum pratense, Festuca pratensis, Trifolium repens)
for high-yielding dairy cows, typically renewed every 6-8 year. The occasional year in between renewal of the pasture 
crop there can be a year with barley.
The UAV flight covers an area which is defined by the following polygon coordinates (latitude, longitude in GCS WGS84, decimal degrees): 
63.811086, 20.237750; 63.810777, 20.239303; 63.810805, 20.240661; 63.809951, 20.243334; 63.806149, 20.232906; 63.808081, 20.229200; 63.811086, 20.237750

FLIGHT PARAMETERS:
75% side and front overlap, nominally. 
Nominal flight height (H) 100 m above ground surface.
Nominal flight speed (V) 8 m s-1.

WEATHER CONDITIONS:
Light conditions during the flight were consistent with complete cloud cover.
Average wind speed (WS) during flight was between 3 - 5 m s-1.
 
SENSOR DESCRIPTION:
Data acquired with a Phantom 4 Multispectral camera. 

GEOREFERENCING: 
Geometric correction performed with 21 Ground Control Points (geometric model RMSE: 0.008 m)
The orthomosaic projection is SWEREF99_TM (EPSG:3006).

PROCESSING METHODS:
Orthomosaic processed using Metashape 1.6.2. 
Details about processing can be found in the Metashape report (SITES_UAV-RGB_RBD_RBDN_20220718_U02.PDF) which is available
within the downloaded .zip folder.

QUALITY CONTROL FLAGGING (QFLAG):
Quality flag value for the RGB flight is 132. First and second digit refers to the radiometric and geometric accuracy respectively while last one remaining 
refers to the presence or absence of visual artificats in the data if any. 
For detailed information about data quality flagging system used within SITES Spectral, refer to this document (SITES Spectral – Data Quality Flagging (QFLAG) Documentation; PID: https://meta.fieldsites.se/objects/yHjlJ9dsmPzMNAGPswfSlEtC)

PERMISSIONS:
This material has been inspected and approved for dissemination by Lantmäteriet.




