READ-ME-FIRST.txt  --  Lab 2 second prepared extract: Landsat 8 red and near-infrared bands, MagicValley
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WHAT THIS IS
  Two single-band GeoTIFF rasters clipped to a study box over MagicValley, from one Landsat 8 scene:
    MagicValley_Red_B4_SR_x10000.tif   Band 4 (red,  0.64-0.67 um) surface reflectance x 10,000
    MagicValley_NIR_B5_SR_x10000.tif   Band 5 (NIR,  0.85-0.88 um) surface reflectance x 10,000
  Pixel type 16-bit signed integer, cell size 30 m, NoData = -32768.
  Coordinate system: WGS 1984 UTM Zone 11N, exactly as USGS delivers the scene. NOTE: this is a
  different UTM zone from the Utah County extract (zone 12). ArcGIS Pro projects on the fly for
  display, but the model's Output Coordinate System environment decides what your outputs get.
  Study box (WGS 84): longitude -114.75 to -114.25, latitude 42.33 to 42.57.

WHERE IT CAME FROM
  Product ID:      LC08_L2SP_040031_20250710_20250715_02_T1
  Satellite/sensor Landsat 8, OLI/TIRS
  Acquired:        2025-07-10, 18:19:56 UTC, WRS-2 path 40 row 31
  Processing:      Collection 2, Level-2 Science Product (surface reflectance), Tier 1
  Cloud cover:     0.01 percent (whole scene)
  Source:          U.S. Geological Survey, distributed through the Microsoft Planetary Computer
                   mirror of the USGS Landsat Collection 2 archive. Retrieved 2026-09-06.
  License:         Landsat data are in the public domain (no restrictions). Please credit
                   "Landsat 8 image courtesy of the U.S. Geological Survey."
  The scene's original metadata file is included unchanged: LC08_L2SP_040031_20250710_20250715_02_T1_MTL.txt

WHAT WE DID TO IT
  1. Clipped bands 4 and 5 to the study box (Clip, cell alignment unchanged).
  2. Applied the Collection 2 Level-2 reflectance scale factor and offset from the metadata file:
        reflectance = DN x 2.75e-05 + (-0.2)
  3. Floored the handful of slightly negative reflectance values at 0 (the Utah County extract does the same).
  4. Multiplied by 10,000 and stored as 16-bit signed integers, LZW compressed.

WHAT WE DID NOT DO
  No resampling, no reprojection, no cloud masking, no filtering. The bands are still integers, so the
  Float step in the lab is still necessary.

HOW TO CITE
  U.S. Geological Survey (2025). Landsat 8 OLI/TIRS Collection 2 Level-2 Surface Reflectance,
  scene LC08_L2SP_040031_20250710_20250715_02_T1. Extract prepared for BYU CE 414, 2026.
