message: Perf: Divide is cheaper than log
diff: @@ -56,7 +56,7 @@ public:
  }
  inline TOutput operator()( const TInput & A ) const
  {
  - return (!A)?0.:TOutput( std::log(m_I0-m_IDark) - std::log( A-m_IDark ) );
  + return (!A)?0.:TOutput( std::log( (m_I0-m_IDark) / ( A-m_IDark ) ) );
  }
  void SetI0(double i0) {m_I0 = i0;}
  void SetIDark(double idark) {m_IDark = idark;}
  