In our podcast, Rudolph Valentino, That Left Eye & More, we pointed out the problem with Valentino's left eye. According to the doctors who made the diagnosis in the Royal Italian Embassy in Los Angeles, he was blind in his left eye.
I think once you are aware of that, it becomes noticeable. In the images below I think we see the left eye out of sync with the right eye and it is an endless credit to him that he so successfully masked this situation.
The pupils should be focused in the same direction which is not the case in reality.
Hear the podcast here: youtube.com/watch?v=5QBbiUFWaoI