Russian surnames ending in -в used to be transliterated for English speakers with ff, e.g. "Petroff" and "Prokofieff". Today v seems more accepted. None of the various modern and historical Romanization systems listed in Wikipedia appear suggest ff.
Was this an exception based on the sound's position at word end? I gather there is a phonological case for using the letter f, but apparently doing so is out of style in the age of formal standards.
Which sort of romanization resulted in the ff and when was it in use?