Dina Temkin contributes a literal version of Mikhail Lozinskij's version (c.1920?) which is at http://lib.ru/SHAKESPEARE/othello2.txt
"Since honor* is a light** of virtue***,Дорогой синьор,
Then your son-in-law is light [as in light-skinned], and by no means black."
* or bravery, heroism, valor, prowess
** or light-source such as a torch
*** or benevolence, wholesomeness
ad hoc version and back-translation by Victor Shapoval (2012)
Коль доблести блеск