This article explains how to convert PlanetScope® data from radiance to reflectance in QGIS using the Raster Calculator.

1. Open QGIS and locate the downloaded data file in the Browser panel.
   
2. Drag and drop the data onto the QGIS canvas.
   
3. Open the Raster Calculator from the Raster menu.
   
4. Extract the top-of-atmosphere (TOA) reflectance coefficients from the metadata file of the downloaded data (the .xml file).
   

   Band 1 reflectance coefficient: 3.62030803777e-05
   Band 2 reflectance coefficient: 3.92650525314e-05
   Band 3 reflectance coefficient: 4.72609117041e-05
   Band 4 reflectance coefficient: 7.48021400215e-05

5. In the raster bands section, each band is named after the raster file, followed by @ and the band number.
   
6. Use the Raster Calculator to multiply the digital number (DN) values in each band by the matching TOA reflectance coefficient.

   "<layer_name>@1" * 3.62030803777e-05
   "<layer_name>@2" * 3.92650525314e-05
   "<layer_name>@3" * 4.72609117041e-05
   "<layer_name>@4" * 7.48021400215e-05

   For example, using the Raster Calculator for band 1:

   
7. Repeat these steps to calculate TOA reflectance values for each remaining band.
   

For more detail, see Converting PlanetScope data from radiance to reflectance.