diff --git a/foa3d/slicing.py b/foa3d/slicing.py
index e6373c5..fef7936 100644
--- a/foa3d/slicing.py
+++ b/foa3d/slicing.py
@@ -211,9 +211,7 @@ def compute_overlap_range(smooth_sigma, frangi_sigma, px_rsz_ratio, truncate=4):
     if smooth_sigma is not None:
         frangi_sigma = np.concatenate((smooth_sigma, frangi_sigma))
 
-    max_sigma = np.max(frangi_sigma)
-
-    ovlp = int(np.ceil(2 * truncate * max_sigma) // 2) if smooth_sigma is not None else 0
+    ovlp = int(np.ceil(2 * truncate * np.max(frangi_sigma)) // 2)
 
     if px_rsz_ratio is not None:
         rsz_ovlp = np.multiply(ovlp * np.ones((3,)), px_rsz_ratio).astype(int)