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I am using google earth engine toolbox to estimate land surface temp for landsat 8 imagery. I have been able to run all the necessary calculation without error but when I add the band as a layer all that is rendered is a solid blue box. I am having trouble determining if it is something that I am doing or an issue with the library itself. I have looked through the code and the calculations seem to be correct.

var geet = require('users/elacerda/geet:geet'); 

var image2 = ee.Image(
  l82.filterBounds(point)
    .filterDate('2018-07-01', '2018-7-31')
    .sort('CLOUD_COVER')
    .first()
);
var new_toa_radiance = geet.toa_radiance(image2, 10);
var brightness_temp_img = geet.brightness_temp_l8c(new_toa_radiance, true);
var l8_ndvi = geet.ndvi_l8(brightness_temp_img); 
var img_pv = geet.prop_veg(l8_ndvi);
var lse = geet.surface_emissivity(img_pv);
var surfTemp_img = geet.surface_temperature_oli(lse);
var im = surfTemp_img.select("LST");
print(im);
Map.addLayer(im, {min: 7000, max: 8000, palette: ['blue', 'green', 'red']});
  • I know you have asked in GitHub's Issues, but I think you should try to reach the author of geet (Eduardo Lacerda) his email is in that site – Rodrigo E. Principe Oct 11 '18 at 19:37
  • I was able to solve the problem, see below. That is a good idea Rodrigo, in the future if I encounter a problem that I can not solve I will take that route. Its an interesting package and hope development continues. – Taylor Oct 11 '18 at 19:43
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To solve this problem I needed to add a stretch to the image layer using the layer settings.

Update

Response from Libraries Author
"The code is right. Make sure your are using the Landsat RAW images! And that after you plot the image you need to set the range of visualization manualy to "Stretch 100%" or something like that. You can do that in the "Layers" button on the map visualization window. If you export the result as an imagem (tif) and load into QGIS you dont need to configure the range, the software will do that for you. :)"

Screen shot of how to apply a stretch

enter image description here

  • Can you include the code for that solution? – Kersten Oct 12 '18 at 7:49
  • 1
    @Kersten This is not a code fix, it is a settings adjustment see above. – Taylor Oct 12 '18 at 16:32

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