diff --git a/mlair/helpers/filter.py b/mlair/helpers/filter.py
index e47364ac7e3184343c402b1949c350048f566e7a..4a6a5044d35d82eaea5a5b7e454771838375b3c5 100644
--- a/mlair/helpers/filter.py
+++ b/mlair/helpers/filter.py
@@ -263,6 +263,9 @@ class ClimateFIRFilter:
                 td_type)
             new_time_axis = np.arange(start, end).astype("datetime64[ns]")
             logging.info(f"{data.coords['Stations'].values[0]}: shape of new_time_axis = {new_time_axis.shape}")
+            logging.info(f"{data.coords['Stations'].values[0]}: start of new_time_axis = {start}")
+            logging.info(f"{data.coords['Stations'].values[0]}: end of new_time_axis = {end}")
+            logging.info(f"{data.coords['Stations'].values[0]}: delta of new_time_axis = {end - start}")
 
             # extract old values to use with new axis
             start = coords[time_dim][-1].values.astype("datetime64[%s]" % td_type) - np.timedelta64(
@@ -272,6 +275,9 @@ class ClimateFIRFilter:
             end = coords[time_dim][-1].values.astype("datetime64[%s]" % td_type)
             new_values = apriori.sel({time_dim: slice(start, end)})
             logging.info(f"{data.coords['Stations'].values[0]}: shape of new_values = {new_values.shape}")
+            logging.info(f"{data.coords['Stations'].values[0]}: start of new_values = {start}")
+            logging.info(f"{data.coords['Stations'].values[0]}: end of new_values = {end}")
+            logging.info(f"{data.coords['Stations'].values[0]}: delta of new_values = {end - start}")
             new_values.coords[time_dim] = new_time_axis
 
             # add new values to apriori