Great question David! If we were able to look into a sunspot without having the surrounding bright surface interfere with our vision, we would actually see something that is not dark. For example, if you plucked a sunspot out of the Sun and placed it in space, it might appear as bright as a full moon. Sunspots are relatively dark compared to the extremely bright photosphere, but they are not dark compared to our normal sense of dark.

Hope that helps!

Holly