diff --git a/notebooks/DynamicFF/Characterize_DynamicFF_NBC.ipynb b/notebooks/DynamicFF/Characterize_DynamicFF_NBC.ipynb
index ef9a5e27f60fd33e4a929c134e1469a467b0e136..2ca437be4e82d851fb5e8d2ab82bc2f4c15953ec 100644
--- a/notebooks/DynamicFF/Characterize_DynamicFF_NBC.ipynb
+++ b/notebooks/DynamicFF/Characterize_DynamicFF_NBC.ipynb
@@ -148,8 +148,7 @@
     "                           include=f\"RAW-R{dark_run:04d}-{file_da}-S*.h5\")\n",
     "\n",
     "    if source_name not in dark_dc.all_sources:\n",
-    "        print(f\"Source {source_name} for module {da} is missed\")\n",
-    "        continue\n",
+    "        raise ValueError(f\"Could not find source {source_name} for module {da} in dark data\")\n",
     "\n",
     "    dark_dc = dark_dc.select([(source_name, image_key)])\n",
     "    conditions = detector.conditions(dark_dc, meta[\"module\"])\n",
@@ -214,8 +213,7 @@
     "                           include=f\"RAW-R{flat_run:04d}-{file_da}-S*.h5\")\n",
     "\n",
     "    if source_name not in flat_dc.all_sources:\n",
-    "        print(f\"Source {source_name} for module {da} is missed\")\n",
-    "        continue\n",
+    "        raise ValueError(f\"Could not find source {source_name} for module {da} in flatfield data\")\n",
     "\n",
     "    flat_dc = flat_dc.select([(source_name, image_key)])\n",
     "    conditions = detector.conditions(flat_dc, meta[\"module\"])\n",