When using the index calculator, the interest is in the reflectance of the terrain. However the pixel value depends on many other factors, which need to be corrected in order to get a measure of the reflectance.
These factors include:
- Incoming light
- Shutter speed
- Sensor response and optical system
When generating the Reflectance Map, Pix4Dmapper uses the values of some parameters present in the EXIF (205732309) of the images in order to correct (at least partially) for the factors mentioned above.
The type of radiometric corrections can be changed in the Processing options: 203891879.