Here is a collection of videos that explain how a person with low vision sees.
It is ofteh nard to explain to other people how you see, but surely these videos are helpful to understand Retinitis PIgmentosa, Stargardt or Macular Degeneration.
The first one has an humorit approach and surely it is not perfect to explain the vision itself, however it helps the viewer to step in the visually impaired person shoes.
Please let us know if you know of any other good video.