Hi everyone,
I am to trying to process LANDSAT satellite images in order to visualize the ground temperature on my project area. To do so, I am using the DF Import LANDSAT Image component of Dragonfly. More specifically, I downloaded the available script from Hydra.
I managed to get a picture of my project’s temperatures, but I have several questions (please redirect me to some documentation if it exists already):
1 // When downloading the GeoTIFF data for a specific scene from GloVis, one gets 12 different TIFF files. I understand that these correspond to 12 different wavelength bands.
I’d like to confirm which band I should use. In the example GH script from Hydra, band 6 is used. For LANDSAT 8, band 6 corresponds to 1.57-1.65µm (short-wave infrared). Is that the revelant band that I should use? (I fear maybe the Hydra script was written for old LANDSAT versions…).
Also, is there scientific doc on why this band is used?
2 // Is there a limitation regarding the size of the map one can create with the DF Import LANDSAT Image component? For some combinations of imageHeight/Width and sampleSize (typically high size and low sample size) the component turns red and returns the following error: 1. Solution exception:math domain error. Why does this error occur?
3 // Existential question: what exactly are the results computed by the component? Are these really the absolute ground temperatures? Are there unmentioned hypothesis contained in the component script (eg. emissivity)?
Many thanks, and have a nice day.
Best,
Julien