So when we were in class the other day we looked at Magic Eye pictures. I couldn't see any other the pictures so I looked into why I couldn't. I found that being able to see the images has to do with the way our eyes work together. If they do not work together and pulling together in unison then our binocular vision is impaired. If you have a misalignment you will not be able to see the image. If you have only one dominant eye than you will not be able to see the image.
Here is advice to see an image