I don't know, if this would qualify as a hallucination but...
Once when my family went out for dinner when I was younger, I snapped a picture with my phones camera when the car stopped at a traffic light then when I looked at the picture later, there was this black shadowy thing near one of the gas pumps at a petrol station. It wasn't smoke I can assure you because, It was dark, really dark -like someone cut out a piece of the night sky without stars and used it- in comparison with the surroundings and it wasn't a smudge because some people could clearly see it too, -shocked expressions.