Question: what happens if you see black spots in front of my eye?

Michael Kelly answered on 25 Jun 2014:

Seeing black spots in your vision is OK providing there is only a few and they haven’t changed much since the last time you noticed them.
One of the things your visual system is very good at is ignoring things that don’t change, so for example you don’t see the shadow that the blood vessels in your eye cast on the photoreceptors. Most of the imperfections in the contents of the eye are ignored. Occasionally if the light comes from an unusual angle or there are no features in the view we see these imperfections. A dim light shone at the side of the eye in a dark room will reveal lots of blood vessels.