Hi,
The case is a bit more complicated that it seems. Satellite images are now in int16 variables but they were acquired with 12-14 bits sensors. That means many of the uint16 DigitalNumbers are empty and one must do contrast stretches to see enhance the data content.
GMT Julia wrappers have tools to deal with this. See
https://www.generic-mapping-tools.org/GMT.jl/dev/gallery/Landsat8/histogram_stretch/
https://www.generic-mapping-tools.org/RemoteS.jl/dev/gallery/L8cube_img/remotes_L8_cube_img/