diff --git a/pydatalab/src/pydatalab/apps/raman_map/blocks.py b/pydatalab/src/pydatalab/apps/raman_map/blocks.py
index 31e198abe..eae2b687b 100644
--- a/pydatalab/src/pydatalab/apps/raman_map/blocks.py
+++ b/pydatalab/src/pydatalab/apps/raman_map/blocks.py
@@ -1,4 +1,5 @@
 import os
+import warnings
 from pathlib import Path
 
 import bokeh
@@ -190,6 +191,10 @@ def generate_baseline(x_data, y_data):
     def generate_raman_map_plot(self):
         file_info = None
 
+        warnings.warn(
+            "The alignment of spectra grid and image cannot yet be guaranteed; please verify any plot you create."
+        )
+
         if "file_id" not in self.data:
             return None
 
diff --git a/pydatalab/src/pydatalab/blocks/common.py b/pydatalab/src/pydatalab/blocks/common.py
index 2b5569e0c..85acaceb0 100644
--- a/pydatalab/src/pydatalab/blocks/common.py
+++ b/pydatalab/src/pydatalab/blocks/common.py
@@ -90,7 +90,7 @@ def load(cls, location: Path) -> pd.DataFrame:
 
             if df.isnull().values.any():
                 warnings.warn(
-                    "Loading file with less strict parser: columns were previously detected as {df.columns}"
+                    f"Loading file with less strict parser: columns were previously detected as {df.columns}"
                 )
                 df = pd.read_csv(
                     location,