diff --git a/Av1an/VMAF/target_vmaf.py b/Av1an/VMAF/target_vmaf.py
index 4739e78..42f727f 100644
--- a/Av1an/VMAF/target_vmaf.py
+++ b/Av1an/VMAF/target_vmaf.py
@@ -1,6 +1,7 @@
 #!/bin/env python
 
 from math import isnan
+from math import log as ln
 
 import subprocess
 from subprocess import STDOUT, PIPE
@@ -210,8 +211,8 @@ def weighted_search(num1, vmaf1, num2, vmaf2, target):
     :return: Q for new probe
     """
 
-    dif1 = abs(-math.log(1-target/100) - (-math.log(1-vmaf2/100)))
-    dif2 = abs(-math.log(1-target/100) - (-math.log(1-vmaf1/100)))
+    dif1 = abs(-ln(1-target/100) - (-ln(1-vmaf2/100)))
+    dif2 = abs(-ln(1-target/100) - (-ln(1-vmaf1/100)))
 
     tot = dif1 + dif2