diff --git a/graxpert/application/app.py b/graxpert/application/app.py
index 0df8ba9..09a4d29 100644
--- a/graxpert/application/app.py
+++ b/graxpert/application/app.py
@@ -91,7 +91,6 @@ def on_bg_tol_changed(self, event):
         self.prefs.bg_tol_option = event["bg_tol_option"]
 
     def on_calculate_request(self, event=None):
-
         if self.images["Original"] is None:
             messagebox.showerror("Error", _("Please load your picture first."))
             return
@@ -114,7 +113,7 @@ def on_calculate_request(self, event=None):
         if self.prefs.interpol_type_option == "AI":
             if not self.validate_ai_installation():
                 return
-        
+
         eventbus.emit(AppEvents.CALCULATE_BEGIN)
 
         progress = DynamicProgressThread(callback=lambda p: eventbus.emit(AppEvents.CALCULATE_PROGRESS, {"progress": p}))
@@ -320,7 +319,8 @@ def on_save_request(self, event):
 
         try:
             self.images["Processed"].save(dir, self.prefs.saveas_option)
-        except:
+        except Exception as e:
+            logging.exception(e)
             eventbus.emit(AppEvents.SAVE_ERROR)
             messagebox.showerror("Error", _("Error occured when saving the image."))
 
@@ -341,7 +341,8 @@ def on_save_background_request(self, event):
 
         try:
             self.images["Background"].save(dir, self.prefs.saveas_option)
-        except:
+        except Exception as e:
+            logging.exception(e)
             eventbus.emit(AppEvents.SAVE_ERROR)
             messagebox.showerror("Error", _("Error occured when saving the image."))
 
diff --git a/graxpert/preferences.py b/graxpert/preferences.py
index 9cba9b1..ab7c2c7 100644
--- a/graxpert/preferences.py
+++ b/graxpert/preferences.py
@@ -96,7 +96,7 @@ def app_state_2_fitsheader(prefs: Prefs, app_state: AppState, fits_header):
         fits_header["SAMPLE-SIZE"] = prefs.sample_size
         fits_header["RBF-KERNEL"] = prefs.RBF_kernel
         fits_header["SPLINE-ORDER"] = prefs.spline_order
-        fits_header["BG-PTS"] = str(app_state.background_points)
+        fits_header["BG-PTS"] = str(list(map(lambda e: e.tolist(), app_state.background_points)))
 
     return fits_header