diff --git a/skyllh/core/pdf.py b/skyllh/core/pdf.py
index a15d669ce6..abecbd2c63 100644
--- a/skyllh/core/pdf.py
+++ b/skyllh/core/pdf.py
@@ -1430,21 +1430,39 @@ def get_pd_with_eventdata(
 
             if self.basis_function_indices is None:
                 with TaskTimer(tl, 'Get basis function indices from photospline.'):
-                    self.basis_function_indices = self._pdf.search_centers(
-                        [eventdata[i] for i in range(0, V)]
-                    )
+                    try:
+                        self.basis_function_indices = self._pdf.search_centers(
+                            [eventdata[i] for i in range(0, V)]
+                        )
+                    except ValueError:
+                        # In case the photospline `search_centers` call fails
+                        # (when `eventdata` is outside photospline boundaries)
+                        # we can fall back to the slower photospline evaluation.
+                        logger.info(
+                            "Falling back to the slower photospline evaluation.")
 
             with TaskTimer(tl, 'Get pd from photospline fit.'):
-                if evt_mask is None:
-                    pd = self._pdf.evaluate(
-                        [eventdata[i] for i in range(0, V)],
-                        [self.basis_function_indices[i] for i in range(0, V)],
-                    )
+                if self.basis_function_indices is not None:
+                    if evt_mask is None:
+                        pd = self._pdf.evaluate(
+                            [eventdata[i] for i in range(0, V)],
+                            [self.basis_function_indices[i] for i in range(0, V)],
+                        )
+                    else:
+                        pd = self._pdf.evaluate(
+                            [eventdata[i][evt_mask] for i in range(0, V)],
+                            [self.basis_function_indices[i][evt_mask] for i in range(0, V)],
+                        )
                 else:
-                    pd = self._pdf.evaluate(
-                        [eventdata[i][evt_mask] for i in range(0, V)],
-                        [self.basis_function_indices[i][evt_mask] for i in range(0, V)],
-                    )
+                    # Falling back to the slower photospline evaluation.
+                    if evt_mask is None:
+                        pd = self._pdf.evaluate_simple(
+                            [eventdata[i] for i in range(0, V)],
+                        )
+                    else:
+                        pd = self._pdf.evaluate_simple(
+                            [eventdata[i][evt_mask] for i in range(0, V)],
+                        )
 
         with TaskTimer(tl, 'Normalize MultiDimGridPDF with norm factor.'):
             norm = self._norm_factor_func(
diff --git a/skyllh/core/signalpdf.py b/skyllh/core/signalpdf.py
index 7170f67cf2..92e39cd479 100644
--- a/skyllh/core/signalpdf.py
+++ b/skyllh/core/signalpdf.py
@@ -833,11 +833,15 @@ def initialize_for_new_trial(
                     tl,
                     'Get and set basis function indices for all PDFs.'):
                 V = self._cache_eventdata.shape[0]
-                bfi = pdf.pdf.search_centers(
-                    [self._cache_eventdata[i] for i in range(0, V)]
-                )
-                for (_, pdf) in self.items():
-                    pdf.basis_function_indices = bfi
+                try:
+                    bfi = pdf.pdf.search_centers(
+                        [self._cache_eventdata[i] for i in range(0, V)]
+                    )
+                    for (_, pdf) in self.items():
+                        pdf.basis_function_indices = bfi
+                except ValueError:
+                    logger = get_logger(f'{__name__}.{classname(self)}.initialize_for_new_trial')
+                    logger.info("Falling back to the slower photospline evaluation.")
 
     def get_pd(
             self,
@@ -1054,11 +1058,15 @@ def initialize_for_new_trial(
                     tl,
                     'Get and set basis function indices for all PDFs.'):
                 V = self._cache_eventdata.shape[0]
-                bfi = pdf.pdf.search_centers(
-                    [self._cache_eventdata[i] for i in range(0, V)]
-                )
-                for (_, pdf) in self.items():
-                    pdf.basis_function_indices = bfi
+                try:
+                    bfi = pdf.pdf.search_centers(
+                        [self._cache_eventdata[i] for i in range(0, V)]
+                    )
+                    for (_, pdf) in self.items():
+                        pdf.basis_function_indices = bfi
+                except ValueError:
+                    logger = get_logger(f'{__name__}.{classname(self)}.initialize_for_new_trial')
+                    logger.info("Falling back to the slower photospline evaluation.")
 
     def get_pd(
             self,
@@ -1112,7 +1120,7 @@ def get_pd(
             pdf_key = self.make_key({'shg_idxs': shg_idxs})
             pdf = self.get_pdf(pdf_key)
 
-            with TaskTimer(tl, f'Get PD values for PDF of SHG {shg_idx}.'):
+            with TaskTimer(tl, f'Get PD values for PDF of SHG {shg_idxs}.'):
                 pd_pdf = pdf.get_pd_with_eventdata(
                     tdm=tdm,
                     params_recarray=params_recarray,