Values in reflectance maps became extreme small (0 – 0.01) when using band images taken by DJI Phantom4 Multispectral. I think it usually take values between 0 and 1. Image Exif contains “Sun Sensor” value and I selected “Sun Irradiance” for the radiometric corrections. Does “Irradiance Gain” in Exif effect? How can I calculate correct reflectance normalized by irradiance?
We will be in contact with you in the internal ticket. I am replying to this for the community: Using radiometric targets will help you get absolute reflectance values from the DJI P4 Multispectral. Please do not leave out the reflectance factors as 0.