If we are far from the light pollution of the city and in a moonless night, we can only see about 2,000 stars of the two hundred billion contained in our galaxy, the Milky Way.
Anyway, it would be impossible for someone to tell because of the eye and muscle fatigue that this would produce.
In astronomical laboratories have the stars through photographs and computer-assisted.
I refer to a video on YouTube, where they will see the size of some stars. No longer seeing please. It will give us what to think about human pride ...
https://www.youtube.com/watch?v=US_O0uK5piA
