Night Vision is released as "free" shareware, i.e. free for private, non-commercial use. Although there is currently no registration fee, if you use the program regularly, the author would appreciate hearing from you! Also contact the author for commercial use.
Night Vision may be freely copied as long as it remains in its
original unmodified form. An exception is made for translations to other
languages. In this case the translation should accurately reflect the
original English version.