The following sections discuss the details of planning a proper data collection mission. In general, increasing image resolution (flying lower and slower) improves the quality of results at the expense of increased time spent flying and processing data. The goal of the operator is to determine an appropriate image resolution to achieve the measurement objective while minimizing the time spent flying and processing.
High quality raw data is essential for accurate results. For airborne multispectral sensors like your SLANTRANGE system, that means imagery with sharp contrast and sufficient resolution to resolve the plants you are measuring, as well as good supporting data on ambient lighting conditions, and the position and attitude of your aircraft at each time of measurement.
The Remote Pilot has control over four aspects of mission planning.
Altitude: set flight altitude based on the size of the plants and the type of data you need to collect (Stress vs. Population Analysis). Automated flight calculators are available in Beyond the Cube's Flight Plan app and the SLANTRANGE app in DroneDeploy.
Speed: set flight speed based on altitude according to the flight calculator, and lighting conditions. Darker, overcast days and morning/evening flights may require slower flight to prevent image blur given the requirement for increased exposure time.
When to fly: determine when to fly based on plant growth stage and weather conditions.
Flight direction: set based on field layout and wind conditions. Fly perpendicular to prevailing winds, and along the crop rows when possible.
For best results, we recommend flights with at least 5 minutes worth of in-flight data. SLANTRANGE systems are optimized for collecting large amounts of data quickly and efficiently. With small area coverage flights that have less than a few hundred images, some data processing steps are not optimized. If flying test plots or other low area coverage crops, we recommend flying lower, slower, and with more overlap, to gather at least 5 minutes worth of in-flight data.