My Leupold VX-6 3-18X50 low light capability seems great. Before mounting on my new rifle, went out at 1\2 hr. after sunset, the time when just the sky has a soft fading blue to black color. As I looked about 50 yds away toward a large oak tree to the West, there was nothing but silhouetted darkness from the canopy with no details. I then grabbed the scope, cranked up the VX-6 to 18 power and was able to discern branches and leaves...not bright or real clear, but Much More Details than possible with my regular naked vision.
If that had been a legal deer during this low twilight, I wouldn't have hesitated to take the shot!