Hello, I’m processing my first maps with the Phantom 4 Multispectral. I flew this mission at 120m, with drone travellin east / west - camera triggered based on time of 2.1 seconds, 70% frond and side overlap. Time was about 7am which might be a bit early but fighting wind most days so trying to go early before it gets to windy. When i process the Multi band tiffs it seems every second row of photos has different exposure and that influences the vegetation indexes. For the record if i reprocess without radiometric correction this disappears, and the RGB Ortho doesn’t have this. I’m wondering if the angle the drone in flight is casuing big differences with the light sensor, and thats the reason for this issue? If so, what is the work around? To have the drone hover and take a photo at each point means you can only map a couple acres on a battery.
here are a few tips to improve your results:
- Higher overlap ~80%
- Fly slower with the P4M
- Fly at least on path extra on every side of your AOI
- Fly as parallel as possible to the sun not direct into the sun. (https://www.suncalc.org)