diff --git a/notebooks/LPD/LPDChar_Darks_NBC.ipynb b/notebooks/LPD/LPDChar_Darks_NBC.ipynb
index 97a2942e2e234822c53c9f4f74e89835929a364f..ed1686ed9c72a2ef7c04631e80c805050f957b93 100644
--- a/notebooks/LPD/LPDChar_Darks_NBC.ipynb
+++ b/notebooks/LPD/LPDChar_Darks_NBC.ipynb
@@ -69,11 +69,11 @@
    "source": [
     "import copy\n",
     "import multiprocessing\n",
-    "import os\n",
     "import warnings\n",
     "from datetime import datetime\n",
     "from functools import partial\n",
     "from logging import warning\n",
+    "from pathlib import Path\n",
     "\n",
     "warnings.filterwarnings('ignore')\n",
     "\n",
@@ -268,7 +268,7 @@
     "\n",
     "inp = []\n",
     "for gg, run_num in enumerate([run_high, run_med, run_low]):\n",
-    "    run_path = os.path.join(in_folder, f\"r{run_num:04d}\")\n",
+    "    run_path = Path(in_folder, f\"r{run_num:04d}\")\n",
     "    for i in modules:\n",
     "        inp.append((run_path, i, gg))\n",
     "\n",
@@ -404,14 +404,14 @@
     "            }\n",
     "        else:\n",
     "            timestamp = mdata.calibration_constant_version.begin_at.isoformat()\n",
-    "            filepath = os.path.join(\n",
+    "            filepath = Path(\n",
     "                mdata.calibration_constant_version.hdf5path,\n",
     "                mdata.calibration_constant_version.filename\n",
     "            )\n",
     "            h5path = mdata.calibration_constant_version.h5path\n",
     "            old_mdata[qm][const] = {\n",
     "                \"timestamp\": timestamp,\n",
-    "                \"filepath\": filepath,\n",
+    "                \"filepath\": str(filepath),\n",
     "                \"h5path\": h5path\n",
     "            }\n",
     "\n",