diff --git a/mlair/helpers/filter.py b/mlair/helpers/filter.py
index 488fdfd30d684516782b67dfc5a417fefee15a6a..9a61de715bc02e57a41ab6c2b9a62de7157acf07 100644
--- a/mlair/helpers/filter.py
+++ b/mlair/helpers/filter.py
@@ -563,8 +563,9 @@ class ClimateFIRFilter(FIRFilter):
 
     def create_visualization(self, filtered, data, filter_input_data, plot_dates, time_dim, new_dim, sampling,
                              extend_length_history, extend_length_future, minimum_length, h,
-                             variable_name, extend_length_opts=0):  # pragma: no cover
+                             variable_name, extend_length_opts=None):  # pragma: no cover
         plot_data = []
+        extend_length_opts = 0 if extend_length_opts is None else extend_length_opts
         for viz_date in set(plot_dates).intersection(filtered.coords[time_dim].values):
             try:
                 td_type = {"1d": "D", "1H": "h"}.get(sampling)
@@ -577,8 +578,6 @@ class ClimateFIRFilter(FIRFilter):
                                                        time_dim,
                                                        new_dim).sel({time_dim: viz_date})
                 else:
-                    # tmp_filter_data = d.sel({time_dim: viz_date,
-                    #                          new_dim: slice(int(-extend_length_history), int(extend_length_future))})
                     tmp_filter_data = None
                 valid_range = range(int((len(h) + 1) / 2) if minimum_length is None else minimum_length,
                                     extend_length_opts + 1)