Folder structure

- `reduced/` — primary reduced spectra (summing, sky subtraction, optimal extraction performed in gui_CR). For each observation: 4 `_master_extracted`  files (one per filter) in FITS format.
- `final_spectra/` — final reflectance spectra (telluric correction, division by solar spectrum, normalization at 1.25 µm).
- `raw/` — raw frames.

Each observation includes the satellite and one or two calibration stars
  (HD 19373, HD 11946, γ Tri).

Sky frames are already subtracted in the `_master_extracted` files and are provided for reference only.