Sounds like I’m getting my books mixed up and I’m really remembering a scene from Temple… but I don’t have copies of either of them anymore so I can’t check for sure.
It was better (or worse) than that! It was a distance of fifteen feet and the assassin is described as being a silhouette. Yet though he is a silhouette the character is able to discern his pale skin, his albino hair, his pink irises and his red pupils.