Bugfix as explained by Slava Turyshev
Bugfix as explained by Slava Turyshev

Bugfix as explained by Slava Turyshev in his mail on 24 July 2017
    # "I realized that the thickness of the Einstein ring seeing by a telescope 
    # is equal to the telescope's aperture. Thus, I was missing a factor of 
    # \sqrt{2} in calculating the equivalent telescope diameter - is is not 
    # 53 km, but 75km.
hippke/communication