Checkout this repository locally:
git clone https://github.com/oirlab/liger-iris-crds-cache
The largest files are not on Github, get them from Galactica at:
/home/azonca/crds_cache/references/tmt/iris
and copy them to the crds_cache/references/ligeriri/iris folder.
Alternatively use Git LFS, see below.
This repository uses Git LFS to store the FITS reference files.
You need to install the git-lfs client and then clone the repository normally to download
the FITS files.